# Forum Home Renovation Roofing  Top plate required on brick work?

## koots

Hi guys.  Just planning some roof work. Will be making a raked/cathedral roof so no bottom chords just ridge beam and rafters. It's a double brick wall that the rafters will sit on and it won't be covered inside - leaving the brickwork visible.   Is it ok to sit the rafters (birdsmouthed of course) straight on the inside skin of brick and secure with hoop iron strapping? Or is it a code requirement to have a top plate for them to sit on? Reason being that with a top plate, the inside wall will go from brick, to the timber top plate, to a big hole above it that will need to be filled with something. If I sit the rafters straight on the brick work I can then have the bricky brick up in between the rafters for a seamless look.  Is this cool or am I missing the reason for top plates? All I can think of is that with a top plate joining all the rafters it would create a stronger connection to the wall? Whereas strapping to the brick leaves each rafter to fend for itself??  Cheers!

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## sol381

use a 38 or 45mm plate on the brickwork...just easier and better for  attaching  the rafters.. you can then use 40mm ceiling battens for your plaster sheeting..if you use 90mm cornice that will cover the gap as well..

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## koots

Thanks mate,  
Just realised I didn't mention - I plan to have exposed rafters, so won't be able to batten out any plaster as this would cover the rafters then. If I were plastering the wall none of this would be a problem as the plaster could just extend up. I've been trying to find some pictures on google of brick walls with the rafters sitting on them. I've found a few, though haven't been able to find out A) how they attached them, though I assume it can only be with hoop iron and B) whether or not there is anything in the building code regarding this. 
I assume people just like to use a plate so they can use triple clamps to attach the rafters easier. I've already had the straps set in to the brickwork so it's no biggie to continue this way.  
I'm thinking perhaps I could use the top plate and set it back slightly, then fill the gap with some nice timber to match the beams perhaps? Anyone seen that done?

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## sol381

just block in between the rafters with the same size timber as the rafters..

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## koots

Sounds like that could be a goer actually. Wasn't sure if there's a better/common way of doing it but it seems that could be it. Thanks bud

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## Micky013

Why cant you top plate on the external leaf rather than internal? Thats hows its done anyway. We just did a lower storey on direct to brick because steel wasnt set up to allow a top plate. IMO i would never do it that way. Rafters not STUCK hard and same for ceiling joists. Top plate allows it all to be positively fixed down then straps and bolts (if required) beef it up.

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## koots

> Why cant you top plate on the external leaf rather than internal? Thats hows its done anyway. We just did a lower storey on direct to brick because steel wasnt set up to allow a top plate. IMO i would never do it that way. Rafters not STUCK hard and same for ceiling joists. Top plate allows it all to be positively fixed down then straps and bolts (if required) beef it up.

  I was under the impression the inner skin is considered the structural skin, in the way that with brick veneer the inside timber frame is considered structural. Is it the outer skin with double brick? Or are they both considered equal (this makes sense to me anyway but I'd read it's inner skin = structural)?

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## Micky013

Every double brick ive done and seen is on external wall. I cant see how a standard rafter would extend out past the external leaf (if pitched from the internal) to create any kind on eave. It would need to be one big ass rafter so you can take a chunk out of the tail to get it over.  
Only time it goes on internal is if there is a gutter over and external boundary wall.  
Would like to know others opinions but i believe its all on the external. I dont think one is more structural than the other as theyre equally built but more for the way the roof works

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## koots

Also the outer skin is the 'wet' skin, so I figured the more you can avoid bolting timber to it the better?

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## koots

In regards to your post about it extending past the external skin, the external skin is just not bricked as high as the inner to account for this? Though I'm assuming in the projects you've worked on (are you a chippie or building trade?) the two skins are equal height and therefore the plate is on the external skin.

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## Micky013

Im a 3rd year adult carpentery apprentice. My house and all the solid brick homes ive seen/been a part of are all bricked to the same level- if anything the internal wall is set slightly lower so not as to interfere. Everything ive seen from WA (virtually 100% double brick) is pitched from the external.  
Dont know what you mean by wet wall but its covered by a roof so at least the top 5 courses will be dry unless you have no eave. The straps are what hold it but in sa your meant to bolt the top plate down.

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## Micky013

Is this extension or new build? Does your engineering or plans specify anything in particular?

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## paddyjoy

> I was under the impression the inner skin is considered the structural skin, in the way that with brick veneer the inside timber frame is considered structural. Is it the outer skin with double brick? Or are they both considered equal (this makes sense to me anyway but I'd read it's inner skin = structural)?

  This is the the case more with multi storey brick buildings, where the inner leaf takes all the floor loads from slabs/joists allowing the outer skin to remain continuous up the building.  Design in Brickwork

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## hotshot

> Im a 3rd year adult carpentery apprentice. My house and all the solid brick homes ive seen/been a part of are all bricked to the same level- if anything the internal wall is set slightly lower so not as to interfere. Everything ive seen from WA (virtually 100% double brick) is pitched from the external.  
> Dont know what you mean by wet wall but its covered by a roof so at least the top 5 courses will be dry unless you have no eave. The straps are what hold it but in sa your meant to bolt the top plate down.

  Hmmm. You can't have seen many houses from WA.  If the house is to have a boxed eave it is generally pitched off the internal skin.  Then the external is set down a number of courses to achieve the desired width for the eave. If the house is to have no eave and a fascia hard up against the wall. Then we will pitch of the external. 
Generally if the brickwork is at the same height there is no structural difference but don't quote me on that coz i haven't seen your plans.  You would pitch it off the external if you planned to have exposed rafters in the eaves. You can still have a boxed eave while pitching off the external but this requires bolting a plate to the wall and is definitely not the quickest way to do it. 
If the roof is pitched off the internal we just cut trimmers in the same size as the rafters to fill it in.

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## hotshot

What kind of eave will you be having?

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## koots

The eave will be exposed rafters. Haven't got detailed drawings yet as I'm still sorting out what timber I'll be using so I can inform the draftsman. He has done an elevation and a cross section at this stage and has advised a top plate on the inner skin of brickwork. The cross section shows the outside skin slightly lower than the inside. It's a gable roof with a 10 degree pitch so not very steep. 
Cheers lads

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## hotshot

Can you post a pic of the elevations?

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## koots

I've cropped it so the detail can be seen regarding the brick and rafters.

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## SteelAUS

I would give Surdex Steel a call, they should be able to give you sound advice. Southern Steel Supplies | Surdex Steel Suppliers | Metal Fabrication

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## intertd6

> Hi guys.  Just planning some roof work. Will be making a raked/cathedral roof so no bottom chords just ridge beam and rafters. It's a double brick wall that the rafters will sit on and it won't be covered inside - leaving the brickwork visible.   Is it ok to sit the rafters (birdsmouthed of course) straight on the inside skin of brick and secure with hoop iron strapping? Or is it a code requirement to have a top plate for them to sit on? Reason being that with a top plate, the inside wall will go from brick, to the timber top plate, to a big hole above it that will need to be filled with something. If I sit the rafters straight on the brick work I can then have the bricky brick up in between the rafters for a seamless look.  Is this cool or am I missing the reason for top plates? All I can think of is that with a top plate joining all the rafters it would create a stronger connection to the wall? Whereas strapping to the brick leaves each rafter to fend for itself??  Cheers!

  .
yes a top plate is required to attach the rafters to with the required hold down methods to resist uplift,  it is acceptable practice, it's not normal or acceptable practice to have the rafters straight on bare masonry or a  plate on the outer skin, as mentioned this skin is external & subject to moisture absorption & therefore the plate would be prone to rotting & premature failure.
inter

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## koots

Thanks mate. That's the sort of answer I was looking for. Having the top plate on the external skin seems so silly to me even if it is done elsewhere. I'm not in the building industry but my knowledge of double brick is that the outside wall is considered a wet wall and therefore would be silly to sit it on there. 
What is the go with old school buildings where the rafters shoot through the bricks in basically the way I was considering, how did they hold them down? Just hoop iron straps?

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## intertd6

> Thanks mate. That's the sort of answer I was looking for. Having the top plate on the external skin seems so silly to me even if it is done elsewhere. I'm not in the building industry but my knowledge of double brick is that the outside wall is considered a wet wall and therefore would be silly to sit it on there. 
> What is the go with old school buildings where the rafters shoot through the bricks in basically the way I was considering, how did they hold them down? Just hoop iron straps?

  Id say the building industry has learnt from its mistakes.
inter

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## hotshot

> .
> yes a top plate is required to attach the rafters to with the required hold down methods to resist uplift,  it is acceptable practice, it's not normal or acceptable practice to have the rafters straight on bare masonry or a  plate on the outer skin, as mentioned this skin is external & subject to moisture absorption & therefore the plate would be prone to rotting & premature failure.
> inter

  I just pitched a roof last week off an external course... So in WA it is acceptable and normal.  If the eaves are exposed your rafter should be minimum h3 treated and so should the plate if pitched off the external.  That should handle any fear of plate rotting. 
I work on double brick homes 90% of the time and been a carpenter for 8 years. But maybe we're just crazy over here.

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## paddyjoy

Our place was built in 1922 with top plate on the external leaf, after nearly 100 years no rot on it.

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## phild01

Never had anything to do with this sort of thing but if the top brick courses are tied together then wouldn't that combination offer far greater strength for roof support, therefore using the external for the top-plate!

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## sol381

In a brick veneer house the frame is built, trusses or rafters are put on the frames and the brickwork is done later.. The external wall carries no weight at all,, not sure why a double brick house would be any different..

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## joynz

> In a brick veneer house the frame is built, trusses or rafters are put on the frames and the brickwork is done later.. The external wall carries no weight at all,, not sure why a double brick house would be any different..

  In a double brick house the brick walls form the structural support as well as the cladding, whereas in a brick veneer house the bricks are used just for cladding.

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## intertd6

> I just pitched a roof last week off an external course... So in WA it is acceptable and normal.  If the eaves are exposed your rafter should be minimum h3 treated and so should the plate if pitched off the external.  That should handle any fear of plate rotting. 
> I work on double brick homes 90% of the time and been a carpenter for 8 years. But maybe we're just crazy over here.

   Ahh WA, they have done some very dodgy things over there that they thought was ok, such as the mortar mix fiasco, they thought that they didn't have to use cement in masonry mortar when this admixture was used!
any how, if you have done your trade, see if you can find some technical drawings from your TAFE training of where shows it's acceptable practice to have a timber plate on an external leaf of masonry, just because it happens doesn't mean it's right unless an architect or engineer specifies it.
from an economic point also it's cheaper to use the inner leaf as the load bearing one, the roof load bearing structure & beams will be 300mm shorter at least each way.
inter

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## toooldforthis

I have only worked on older (1930-1950s) double brick in WA.
inner leaf was the structural.

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## sol381

i Think drilling in to brickwork in a single course will either crack the brick of loosen the brick from the mortar.. what ive seen is a cyclone rod attached to the slab and brought through the cavity..the top plate which can be around 150mm wide can then be tied down through the rod..just one option that may work..

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## Micky013

> Ahh WA, they have done some very dodgy things over there that they thought was ok, such as the mortar mix fiasco, they thought that they didn't have to use cement in masonry mortar when this admixture was used!
> any how, if you have done your trade, see if you can find some technical drawings from your TAFE training of where shows it's acceptable practice to have a timber plate on an external leaf of masonry, just because it happens doesn't mean it's right unless an architect or engineer specifies it.
> from an economic point also it's cheaper to use the inner leaf as the load bearing one, the roof load bearing structure & beams will be 300mm shorter at least each way.
> inter

  I must say how surprising it is that i couldn't find much info regarding double brick construction. Couldn't see anything in timber framing code, absolutely no mention at all in my tafe books but there were illustrations in my Australian HouseBuilding Manual by Allan Staines. The book showed all pitching from innerwall. No exact reason or standards sited but everything was shown pitched off either inner or across both walls with a 120/35. So i can eat my words i spose. Wonder why its still so common to go off outside and why some old houses (inc mine 100yrs plus and mums about 50 plus) are pitched that way? 
Do you have any standards or info on this? Id be interested to read it? 
Cheers

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## intertd6

> I must say how surprising it is that i couldn't find much info regarding double brick construction. Couldn't see anything in timber framing code, absolutely no mention at all in my tafe books but there were illustrations in my Australian HouseBuilding Manual by Allan Staines. The book showed all pitching from innerwall. No exact reason or standards sited but everything was shown pitched off either inner or across both walls with a 120/35. So i can eat my words i spose. Wonder why its still so common to go off outside and why some old houses (inc mine 100yrs plus and mums about 50 plus) are pitched that way? 
> Do you have any standards or info on this? Id be interested to read it? 
> Cheers

  my TAFE stuff is buried somewhere, but have a look at the acceptable standards of domestic construction publication, it's in there as well as I have shown.
inter

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## Micky013

Thanks Inter

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## hotshot

Ahh yes because nsw hasn't lost a couple of hundred homes to fires due to bad insulation practice or have the worst building certification in Australia.  Not everywhere is perfect, things happen we learn. 
The house last week was designed by an architect and passed by an engineer.  
In double brick construction both walls are built exactly the same apart from the fact that one leaf is built on the slab and the other sits on the footings. Both are considered structural and load bearing. Just cause it is more common to be pitched off the internal does not mean it is unacceptable. 
Can you post any details where it says rooves shall only only be pitched off the inside course?  I don't have a copy of the acceptable standards you mention but when i googled it the section for rafters did not say. Roof must be pitched off internal. 
Its pretty hard to find any details about double brick construction but I'm trying to get my hands on the standards AS 4773. 
I can't really take the picture you have posted as support since the eave detail is what I would call unacceptable.  The soffit bearer should continue into the other wall. since it doesn't specify the fascia to be structural. 
Would be great if you can provide some concrete evidence in the BCA or AS standards though, as that would be a great tidbit to shove up some of these big builders.

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## sol381

there are many ways to do soffit.. that is one of them and probably the most popular method up here.  why would the fascia be load bearing..The soffit bearer as they call it is usually nailed to the side of the truss tail..Most times metal facscia is used and the only weight it carried is the soffit which is very light anyway..

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## intertd6

> Ahh yes because nsw hasn't lost a couple of hundred homes to fires due to bad insulation practice or have the worst building certification in Australia.  Not everywhere is perfect, things happen we learn. 
> The house last week was designed by an architect and passed by an engineer.  
> In double brick construction both walls are built exactly the same apart from the fact that one leaf is built on the slab and the other sits on the footings. Both are considered structural and load bearing. Just cause it is more common to be pitched off the internal does not mean it is unacceptable. 
> Can you post any details where it says rooves shall only only be pitched off the inside course?  I don't have a copy of the acceptable standards you mention but when i googled it the section for rafters did not say. Roof must be pitched off internal. 
> Its pretty hard to find any details about double brick construction but I'm trying to get my hands on the standards AS 4773. 
> I can't really take the picture you have posted as support since the eave detail is what I would call unacceptable.  The soffit bearer should continue into the other wall. since it doesn't specify the fascia to be structural. 
> Would be great if you can provide some concrete evidence in the BCA or AS standards though, as that would be a great tidbit to shove up some of these big builders.

   In your case the architect & engineer by design have made it acceptable which is possible as I explained before, a builder can't do this, they have to follow acceptable convention, in building not everything is written, drawings & details of drawings are a major component of acceptable practices & standards & form the majority of contract documentation. The relevant parts of the BCA & standards are referenced in the publication. There are couple of logical reasons why the inner leaf of masonry has evolved to be the load bearing one, it's cheaper & it's more durable in the long term
The dodgy insulation fires was a AU wide problem & not related to acceptable building practices relevant at the time, they have since been amended because of the pink batts fiasco.
Show us some figures of NSW having a worse record percentage wise per builder in domestic construction than any other state for certification, I can tell you now using the outer leaf of cavity masonry construction for load bearing in NSW is a rarity & the lenders would defect the works if done by a builder & more than likely suspended progress payments.
inter

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## hotshot

> In your case the architect & engineer by design have made it acceptable which is possible as I explained before, a builder can't do this, they have to follow acceptable convention, in building not everything is written, drawings & details of drawings are a major component of acceptable practices & standards & form the majority of contract documentation. The relevant parts of the BCA & standards are referenced in the publication. There are couple of logical reasons why the inner leaf of masonry has evolved to be the load bearing one, it's cheaper & it's more durable in the long term
> The dodgy insulation fires was a AU wide problem & not related to acceptable building practices relevant at the time, they have since been amended because of the pink batts fiasco.
> Show us some figures of NSW having a worse record percentage wise per builder in domestic construction than any other state for certification, I can tell you now using the outer leaf of cavity masonry construction for load bearing in NSW is a rarity & the lenders would defect the works if done by a builder & more than likely suspended progress payments.
> inter

  https://www.engineersaustralia.org.a...-june_2013.pdf.  It may have been a problem for AU. But I didn't hear of any issues in Perth.  But you can quote something from years ago about WA but I say something about NSW and blow it off.  Point is what happens in either state is not the be all and and all. 
Can you link me to the relevant clause or standards? As i said I don't have this publication.  And i follow the BCA and standards.  
Just cause it's rare does not mean its unacceptable. What about when houses have a wrap around verandah do you also only pitch of the internal? 
In Perth double brick construction each leaf is built exactly the same. There is no difference structurally. 
Your argument is I haven't seen a drawing/detail so it is unacceptable.  Just because you haven't seen it doesn't mean its acceptable just not common.  I agree economically it is better.  But to argue durability when others in this thread have stated they live/know of houses 50-100 years old pitched off the external disproves that comment. 
As I've said before I'd love for you to show where in the standards and BCA it says "you may not pitch off the external leaf".  As this would be really interesting due to how common it is here. Cheers

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## intertd6

> https://www.engineersaustralia.org.a...-june_2013.pdf.  It may have been a problem for AU. But I didn't hear of any issues in Perth.  But you can quote something from years ago about WA but I say something about NSW and blow it off.  Point is what happens in either state is not the be all and and all. 
> Can you link me to the relevant clause or standards? As i said I don't have this publication.  And i follow the BCA and standards.  
> Just cause it's rare does not mean its unacceptable. What about when houses have a wrap around verandah do you also only pitch of the internal? 
> In Perth double brick construction each leaf is built exactly the same. There is no difference structurally. 
> Your argument is I haven't seen a drawing/detail so it is unacceptable.  Just because you haven't seen it doesn't mean its acceptable just not common.  I agree economically it is better.  But to argue durability when others in this thread have stated they live/know of houses 50-100 years old pitched off the external disproves that comment. 
> As I've said before I'd love for you to show where in the standards and BCA it says "you may not pitch off the external leaf".  As this would be really interesting due to how common it is here. Cheers

  We are still waiting for your evidence that contradicts the published & industry acceptable practice.
As said architects & engineers have the ability to go around & beyond acceptable practice but it's not the norm so anything is vertually possible, the main home loan lenders include references to acceptable standards of construction in their lending conditions, so if the standard of the work or workmanship isnt acceptable the money is stopped, if they were to deem it unacceptable they have a document to back them up,  one major lender used to co-produce the acceptable standards of construction publication.
It all relates to the golden rule, "those with the gold rule"
inter

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## hotshot

At the minute the only evidence I can bring is anecdotal of my experience and since I live in WA where double brick is king.  May i ask what your qualifications are? 
All you have supplied is one picture which shows a a poor building practice eave detail and for a boxed eave.  Where as we are talking about exposed rafters in the eave I don't think you can argue is relevant. 
If you can show me anywhere it says rooves must not be pitched off external wall. I will eat my hat and I will send you a carton of the finest beer.  But don't continue to quote from one book that is a "reference book" not a code or standard.  and showing a picture which is not relevant. 
I can point to the following building/ display homes by builders in WA where the grooves are pitched off the external wall in some parts of the roof. Ie over carports where it is more financially viable to not have eaves. Harper | Celebration Homes https://www.summithomes.com.au/new-home-designs/alkira https://www.newgenerationhomes.com.a...esigns/oceanic The Luxor Display Home | Ventura Homes Portfolio Residential St. Ali II | Dale Alcock Homes 
All these are pitched off external in some parts of the roof. please tell me why they are still being produced if they are so unacceptable and why banks keep giving people loans to buy these house. 
Unless you can show me somewhere where it says this is unacceptable.  Then I'm just gonna assume you are sprouting your opinion as fact after reading a reference book. 
I'd be happy to be proven wrong and Ill eat my hat. But why if it is so unacceptable is it so common here?  Where all we do is build double brick homes.  House after house is being built on small blocks with flush eaves, pitched off the external.

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## hotshot

Just googled the book you have referenced. Which states the standards of domestic construction in NSW not for all Australia.  As NSW does not build predominately with brick it stands to reason that it may not cover all acceptable practices for double brick. You may try argue that in NSW it is not common practice but I think to say for Australia in general to sprout it is unacceptable is wrong.

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## intertd6

> At the minute the only evidence I can bring is anecdotal of my experience and since I live in WA where double brick is king.  May i ask what your qualifications are? 
> All you have supplied is one picture which shows a a poor building practice eave detail and for a boxed eave.  Where as we are talking about exposed rafters in the eave I don't think you can argue is relevant. 
> If you can show me anywhere it says rooves must not be pitched off external wall. I will eat my hat and I will send you a carton of the finest beer.  But don't continue to quote from one book that is a "reference book" not a code or standard.  and showing a picture which is not relevant. 
> I can point to the following building/ display homes by builders in WA where the grooves are pitched off the external wall in some parts of the roof. Ie over carports where it is more financially viable to not have eaves. Harper | Celebration Homes https://www.summithomes.com.au/new-home-designs/alkira https://www.newgenerationhomes.com.a...esigns/oceanic The Luxor Display Home | Ventura Homes Portfolio Residential St. Ali II | Dale Alcock Homes 
> All these are pitched off external in some parts of the roof. please tell me why they are still being produced if they are so unacceptable and why banks keep giving people loans to buy these house. 
> Unless you can show me somewhere where it says this is unacceptable.  Then I'm just gonna assume you are sprouting your opinion as fact after reading a reference book. 
> I'd be happy to be proven wrong and Ill eat my hat. But why if it is so unacceptable is it so common here?  Where all we do is build double brick homes.  House after house is being built on small blocks with flush eaves, pitched off the external.

  i can only state what is the industry acceptable practice & supply information to back that up, plus give reasons where that acceptable practice may be altered, it may not be actually stated but it is definitely drawn that way.
My qualifications are as follows, trade qualified carpenter, held a builders license for over 15 years, tertiary trained in building & construction so I have letters after my name, plus started in the game around 1977, working in 2 man teams through to the largest builders in the country in most of the states & territories. I was designing & building houses for clients a year after finishing my apprenticeship.
You still haven't produced a drawing from your training or anywhere showing that carpenters are formally trained from recognised institutions to pitch roofs off the external leaf of cavity masonry. What are your formal qualifications? 
Inter

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## Marc

I see that Inter bashing continues. Let it go Inter, not worth it.

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## sol381

I dont see any evidence from any of those pictures that the external wall is load bearing..it just shows in most cases that there is no eaves..it just shows that the truss tails have been cut short and end in line with the external brickwork..plenty of that up here but the internal frame still supports the roof..

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## pharmaboy2

> there are many ways to do soffit.. that is one of them and probably the most popular method up here.  why would the fascia be load bearing..The soffit bearer as they call it is usually nailed to the side of the truss tail..Most times metal facscia is used and the only weight it carried is the soffit which is very light anyway..

  in my Reno just starting, the fascia on the corners and the cantilevered corners are all getting 140/45 f17 lvl to tie the flying rafters.   That's for 900mm eaves on a 7d roof in an N4 site.   Soffit isn't light when it's copping 150kmh winds I suppose  :Wink:

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## sol381

N4 in newcastle.. mm, didnt think it got that windy down there.. anyway.. gotta do what the engineer says..

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## pharmaboy2

^^^ engineers aren't known for their risk taking.....(except at university when it involves alcohol intake).  It's not Newcastle ( well it sort of is, seem to have these eastern lows that come together every 7 or 8 years lately)it's the site as well facing SE, top of hill, well above surrounding, hill 20% slope etc etc. 
the storms exactly a year ago wreaked havoc, how about trees 2 ft diameter snapped off 15 feet in the air!

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## sol381

good lord.. well better to overdo i guess..so are you using 140 x 45 as fascia..wont leave much room under to attach soffit will it.. wouldnt 180x 25 fascia be ok...

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## pharmaboy2

Ah, it won't be the fascia, it's an end beam to hold the flyers and rafters.  We are getting fascia folded out of colorbond for the cover.  big overhangs that are as thin as possible, but can cope with the storms 
(hoping that makes sense - terms not correct)

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## hotshot

> i can only state what is the industry acceptable practice & supply information to back that up, plus give reasons where that acceptable practice may be altered, it may not be actually stated but it is definitely drawn that way.
> My qualifications are as follows, trade qualified carpenter, held a builders license for over 15 years, tertiary trained in building & construction so I have letters after my name, plus started in the game around 1977, working in 2 man teams through to the largest builders in the country in most of the states & territories. I was designing & building houses for clients a year after finishing my apprenticeship.
> You still haven't produced a drawing from your training or anywhere showing that carpenters are formally trained from recognised institutions to pitch roofs off the external leaf of cavity masonry. What are your formal qualifications? 
> Inter

  
I don't have the years that you do but I'm a qualified carpenter and all going well I will have finished my diploma in building at the end of the year.  With the intention of gaining my licence after another couple of years of running my carpentry business.  Have spent have my half time working on high end project builders and the other for smaller builders who concentrate on renovations and extensions. 
I'm not trying to 'bash' anyone. But in my experience with double brick construction pitching off the external is perfectly acceptable as both walls are built the same.  This is the way every carpenter in WA is taught.  You can take my word for it or not but all those buildings will be pitched off the external.  You state that it is industry standard but your only suppling a reference book that is from NSW.  I'm saying that is acceptable and there are couple of others in this thread also stating they have it on their house which I think says something. 
As I said if you could show me where in the code it says you can't id like to see.  But it seems we will not agree. So *handshake*, agree to disagree.

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## hotshot

> I dont see any evidence from any of those pictures that the external wall is load bearing..it just shows in most cases that there is no eaves..it just shows that the truss tails have been cut short and end in line with the external brickwork..plenty of that up here but the internal frame still supports the roof..

  The internal frame? What on brick veneer?... we are discussing double brick. 
We stick frame 99% so no trusses So the rafters tails are precut.  I don't gain anything by making up stories.  So take it as you like.

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## pharmaboy2

I'm quite sure no one is lying here, but I can see why internal skin supporting is the drawing detail of default. 
first, outdoor skin is on full damp course - this must increase earthquake risk because the roof would move at a different rate to the masonry - saw this in the Newcastle earthquake, where really a great number of older double brick buildings were lost compared to almost nil brick veneer domestic dwellings.  
Fire rating - surely it is more complicated with structural roof members to the very outside of the building envelope. 
consistantcy - floors are supported off the internal skin for obvious reasons. 
tie downs in higher wind areas - all the tie down details show tie downs going through the cavity on the outside of the plate on top of the internal skin. 
i think the biggest disadvantage, is the effect of damp course on earthquake viability. If that outer skin slides off the footing at damp course it will take the roof with as it inevitably collapses, the roof landing on the internal at best which would be a total loss structurally. 
but at the same time I've long thought double brick in general is a poor building design - far too rigid to cope with earth movement

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## Micky013

> I'm quite sure no one is lying here, but I can see why internal skin supporting is the drawing detail of default. 
> first, outdoor skin is on full damp course - this must increase earthquake risk because the roof would move at a different rate to the masonry - saw this in the Newcastle earthquake, where really a great number of older double brick buildings were lost compared to almost nil brick veneer domestic dwellings.  
> Fire rating - surely it is more complicated with structural roof members to the very outside of the building envelope. 
> consistantcy - floors are supported off the internal skin for obvious reasons. 
> tie downs in higher wind areas - all the tie down details show tie downs going through the cavity on the outside of the plate on top of the internal skin. 
> i think the biggest disadvantage, is the effect of damp course on earthquake viability. If that outer skin slides off the footing at damp course it will take the roof with as it inevitably collapses, the roof landing on the internal at best which would be a total loss structurally. 
> but at the same time I've long thought double brick in general is a poor building design - far too rigid to cope with earth movement

  The external wall is tied to the internal wall with brick ties. If the external was to "slide off" the footing surely it would cause irreparable damage to the internal so i dont see much difference.  
In sa tie downs are straps that must be a minimum 9 courses down the cavity either pinned to both leaves of brick or folded into the wall min of 50mm i recon so cant see how it would be any different if pitched of the internal vs external.

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## hotshot

> I'm quite sure no one is lying here, but I can see why internal skin supporting is the drawing detail of default. 
> first, outdoor skin is on full damp course - this must increase earthquake risk because the roof would move at a different rate to the masonry - saw this in the Newcastle earthquake, where really a great number of older double brick buildings were lost compared to almost nil brick veneer domestic dwellings.  
> Fire rating - surely it is more complicated with structural roof members to the very outside of the building envelope. 
> consistantcy - floors are supported off the internal skin for obvious reasons. 
> tie downs in higher wind areas - all the tie down details show tie downs going through the cavity on the outside of the plate on top of the internal skin. 
> i think the biggest disadvantage, is the effect of damp course on earthquake viability. If that outer skin slides off the footing at damp course it will take the roof with as it inevitably collapses, the roof landing on the internal at best which would be a total loss structurally. 
> but at the same time I've long thought double brick in general is a poor building design - far too rigid to cope with earth movement

  Yea my point being just because its the default doesn't mean its the only acceptable way. There's more than one way to skin a cat.  
Re fire rating thats irrelevant as the roof is members finish at the same point regardless of external and internal. 
Since the brickwork is all tied in to each other wouldn't the internal wall go with it in the case of an earthquake. Hence no difference. 
To be honest it just seems like common sense to me. That in certain situations pitching off the external is a better way to build. Ie in the case of the OP.  And at least in WA it is 100% acceptable.  
I don't disagree that double brick is a poor method of construction and I'm hoping eventually we'll move away from it especially in regards to becoming more energy efficient. 
Though I don't think this method will change as the largest builders in WA come from bricklaying backgrounds. And all they offer is double brick for an affordable price.

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## sol381

I think koots has gone and checked into a mental home after seeing all this..

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## intertd6

> I don't have the years that you do but I'm a qualified carpenter and all going well I will have finished my diploma in building at the end of the year.  With the intention of gaining my licence after another couple of years of running my carpentry business.  Have spent have my half time working on high end project builders and the other for smaller builders who concentrate on renovations and extensions. 
> I'm not trying to 'bash' anyone. But in my experience with double brick construction pitching off the external is perfectly acceptable as both walls are built the same.  This is the way every carpenter in WA is taught.  You can take my word for it or not but all those buildings will be pitched off the external.  You state that it is industry standard but your only suppling a reference book that is from NSW.  I'm saying that is acceptable and there are couple of others in this thread also stating they have it on their house which I think says something. 
> As I said if you could show me where in the code it says you can't id like to see.  But it seems we will not agree. So *handshake*, agree to disagree.

   There are quite a few differences & advantages of why the inner leaf is the load bearing & the acceptable method, I mentioned durability which you took as only impacting the timber elements, the external leaf of masonry is less durable than the inner with exposure to weathering & chemical attack with material failures common place, so also high walls are broken by floors giving a strength advantage to the inner skin, the unbroken outer skin is too slender & can't resist the same forces over the same heights, add in the possibility of material failures makes it an unacceptable option without expensive engineering or material features for the long term serviceable life of the structure. There are thousands apon thousands of home units being built in in Sydney at this very moment using the acceptable method of cavity construction where the inner leaf is load bearing, I haven't seen any using your regional method but I will keep an eye out for it to see if it's taking off.
inter

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## UseByDate

> ^^^ engineers aren't known for their risk taking.....(except at university when it involves alcohol intake).  It's not Newcastle ( well it sort of is, seem to have these eastern lows that come together every 7 or 8 years lately)it's the site as well facing SE, top of hill, well above surrounding, hill 20% slope etc etc. 
> the storms exactly a year ago wreaked havoc, how about trees 2 ft diameter snapped off 15 feet in the air!

  Hmmmm.
 I agree that engineers try to minimise risk but I don't agree that they are not risk takers.  The majority of astronauts are 	engineers.Virtually all aircraft test pilots 	are engineers.  	Engineers are responsibly for 	designing and developing unique systems/machines/techniques. Failure 	could result in personal career destruction, bankruptcy of a company 	employing thousands of workers, or the death of many people.To say nothing of military 	engineers.

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## intertd6

> Hmmmm.
>  I agree that engineers try to minimise risk but I don't agree that they are not risk takers.  The majority of astronauts are     engineers.Virtually all aircraft test pilots     are engineers.Engineers are responsibly for     designing and developing unique systems/machines/techniques. Failure     could result in personal career destruction, bankruptcy of a company     employing thousands of workers, or the death of many people.To say nothing of military     engineers.

  i think PB was referring to CPE (chartered practicing engineers, structural ones at that) they don't fly by the seat of their pants, if they stuff up then thousands Of lives could be lost in a catastrophic failure & they would be sent to the big house for a very very long time.
inter

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## UseByDate

> i think PB was referring to CPE (chartered practicing engineers, structural ones at that) they don't fly by the seat of their pants, if they stuff up then thousands Of lives could be lost in a catastrophic failure & they would be sent to the big house for a very very long time.
> inter

  I am not familiar with the term charted practicing engineer so I googled the internet and came up with the following quote. Do you mean Charted Professional Engineer or are both descriptions used?   A Chartered Structural Engineer is a suitably qualified professional person who deals with the design, construction and maintenance of buildings.  He or she will be a member, or a fellow, of the Institution of Engineers Australia and will have one of the following sets of initials after his or her name; MIEAust, FIEAust. Building related structural certification and specifications will only be accepted by local council if carried out by a Chartered Professional Engineer (CPEng) that is on the National Professional Engineer Register (NPER).

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## Marc

> I am not familiar with the term “charted practicing engineer” so I “googled” the internet and came up with the following quote. Do you mean “Charted Professional Engineer” or are both descriptions used?   “A Chartered Structural Engineer is a suitably qualified professional person who deals with the design, construction and maintenance of buildings.  He or she will be a member, or a fellow, of the Institution of Engineers Australia and will have one of the following sets of initials after his or her name; MIEAust, FIEAust. Building related structural certification and specifications will only be accepted by local council if carried out by a Chartered Professional Engineer (CPEng) that is on the National Professional Engineer Register (NPER).”

  Considering that English was my 4th language in the lineup of learning and I missed a few classes, I may be wrong here but it must be a rather large engineer to need to be charted ...  :Smilie: 
"Instructions when you go to the loo ... take a bearing on the belly button in a southerly direction and extend the line over the horizon and you can not miss it ... "

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## UseByDate

> Considering that English was my 4th language in the lineup of learning and I missed a few classes, I may be wrong here but it must be a rather large engineer to need to be charted ... 
> "Instructions when you go to the loo ... take a bearing on the belly button in a southerly direction and extend the line over the horizon and you can not miss it ... "

  Whoops. :Doh:

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