# Forum Home Renovation Roofing  Rafter to beam connection at an angle - approx 100 degrees.

## Dr - 307

Hi guys, 
Have a dilemma. May be building a deck and pergola for a friend and the opposite boundary of the pergola from the house isn't parallel to the house. I reckon it's around about the 10 degree mark off parallel to the house. 
Joist / rafter hangers are normally used when the pergola has opposing fascias or beams parallel to one another and their rafters run perpendicular to the fascia or beam.
Is there a hanger that is adaptable to angles? I don't want to skew nail.
For the deck it's not an issue. Joists will sit over the bearer and I'll string line and trim them at whatever angle I want.
At the house the rafter will run off perpendicular to the house's fascia so standard hangers will be used.  The rafter to the opposing fascing beam connection is the issue.  *So, is there some method of connecting rafters to fascias or beams at an angle other than skew nailing?* 
Your help would be appreciated,
A pondering Dr - 307. :Confused:

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## journeyman Mick

Use multigrips. Like a trip-L-grip anchor but you can bend it a bit to the required angle. Check out pg 22 in the Pryda catalogue. 
Mick

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## Dr - 307

Thanks for your reply Mick.
What about if my rafters are going to be 190 x 45?  I took a look and what you suggested are on the small side.  I could use two per side but isn't there a hanger of some sort? 
Doc. :Confused:

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## DvdHntr

Use a plain metal angle to support the load and either multigrips or cyclone tie to hold it in place. Or you could use a cyclone tie around the other way to hold it up and one in the normal way to hold it down. But the metal angle is the better option.

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## Dr - 307

You mean nomal metal angle at whatever size I think I might need, pry it open to whatever angle I require and bolt it into the side of the rafter?

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## journeyman Mick

No, I think he means sit the rafter on top of the heavy metal angle (this takes most of the downwards load) and fix the multi grips to the side to stop it canting over and also further fix it. 
Mick

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## Dr - 307

How about I run a ledger along the beam, house out my rafters to sit on the ledger and then slam a couple of nails in.  I know I said I didn't want to skew nail but with the rafter sitting on the ledger I think it will look neater and cleaner and of course be structually sound. 
Doc.

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## DvdHntr

Use the ledger and the multigrips. Most of the time there is an problem with ledgers so I went with a metal angle option. If the ledger will work then use it. 
You will need tie downs so I would use the multigrip instead of the skew nails.

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## Ivan in Oz

> Use the ledger and the multigrips. 
OK!
I know what Multi-Grips are....... 
The LEDGER, 
Is that like a thickened Facia Board? 
Please be gentle and answer in ONE syllable words :Wink:

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## echnidna

Whats wrong with skew nailing it then strapping it with some hoop iron?

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## Dr - 307

Hoop iron - I think that will look a little rough, but I appreciate the suggestion. 
Ledger - I was going to try and explain it but thanks to resident decking expert 'utemad' a picture will explain it perfectly.   
That smaller section piece of wood screwed in at the bottom edge of the larger one that's bolted in to the brick is the ledger. See how he's housed out his joists? It allows the joist to sit soundly if you weren't using joist hangers. He showed us this example as an idea for getting around having to use stainless steel hangers around pool areas which can get expensive. What is also important when using this method is that you don't remove more than 1/3rd of the width of the timber. What he's done is perfect. 
That's what I will do to the rafters at the correct angle of course ....... and for piece of mind (and fear of no one helping me again if I don't take their advice  :Rolleyes:  ) I will use multigrips to tie it down. 
Happy to help and thanks for the help guys  :2thumbsup: , 
Dr - 307. :Cool:

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## ausdesign

DR, the ledger will work fine. It won't do anything but position the rafters for you.
If there's no roofing [pergola not verandah etc] then the skew nailing will be sufficient. - no uplift to take into consideration.
If the area is to be sheeted then you need to look at some form of 'triple grip' setup to provide for uplift & the nailing requirement will be governed by the roof area, spacing of rafters & the 'design wind gust speed'.

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## Dr - 307

OK. 
Explain this then. How about when I see sheeted pitched (gable or hip) verandahs and they've used - no ledger to support the rafter and no multi or triple grip to fasten it. 
How do they do it? Are they simply skewing a couple nails in or using some other method we don't know about. And I don't mean in backyards either. I'm talking about in parks, council / public areas. I can't remember seeing a joist hanger or grip of some sort used anywhere. 
This roof will be lined with a combination of steel and polycarb sheeting. I thought that by using the ledger to take the weight then 3 x 4" nails would do the trick. Triplegrips won't work either because they won't sit on the ledger and get fastened to the rafter and beam properly. In regards to multigrips, I've always looked at them as being a flexible / more adaptable solution to the triplegrip because I thought that the split in the multigrip was a weak point and therefore would not be suitable to a 'two face' connection. 
More information......pleeeease  :Cry: .

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## billbeee

Dr,
You got the answers with your first replies, use multigrips/triple grips.
Support the floor joists on an angle. 
"Is there a hanger that is adaptable to angles? "
If you really want to use joist hangers cut the things in half on the bottom. Fix each side and wack in a couple of decent teks underneath.
Even use two to make one, that way you have a full lap at bottom. P.O.P. 
Cheers
Bill

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## thebuildingsurv

3 x 150mm bugle screws should do it, screw from the side beam into the rafter ends ensuring they dont split, talk tour your building inspector assuming you have a permit. As an engineer what would your opinion be on that method dvdhntr ?

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## DvdHntr

That sounds feasible but I just assumed that he wouldn't want to have the screws in from the other end. He also has to make sure that the gauge of the screws is small enough to not promote splitting and that he remembers that screws into end grain only give 60% of the capacity of screws into side grains. 
I would not recommend cutting up joist hangers as they are only thin gauged steel and the underside steel would be likely to bend. 
There are many other solutions, it all comes down to which is cheapest and easiest, and still structurally sound. He could always pack out locally behind each joist with ply so that the joists are perpendicular with the ply and connect all three together with longer nails than supplied to get enough fixing into the beam through a joist hanger.

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## Dr - 307

*Billbee,*
It's actually rafters I'm hanging this time so the angle bracket will look terrible.  *thebuildingsurv,*
Can't screw in from the beam into the end grains 'cause there is no access. The beam opposite the house fascia runs along the property perimeter and in some parts along the neighbouring property's garage.  *DvdHntr,*
If bugle screwing through the end grains is feasable, isn't skew bugle screwing through the side grains also feasable?
And what gauge would be appropriate for F5 Seasoned TP rafters 190 x 45?  *And what of this as a matter of interest.....*
How about when I see sheeted pitched (gable or hip) verandahs and they've used - no ledger to support the rafter and no multi or triple grip to fasten it. 
How do they do it? Are they simply skewing a couple nails in or using some other method we don't know about. And I don't mean in backyards either. I'm talking about in parks, council / public areas. I can't remember seeing a joist hanger or grip of some sort used anywhere. 
Cheers boys, keep it coming, 
Dr - 307.  :2thumbsup:

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## ausdesign

The uplift capacity required for the joint is determined by the design wind gust speed for your area.
i.e. for a N2 site [in melb] the uplift pressure per joint for seasoned pine is approx. 0.74 kPa for a sheet roof.
Multiply the roof area held by the connection by 0.74
i.e rafter span 2.4m at 900 spacings = 1.2 x .9 x .74. 
Equals 0.799 uplift capacity required.
2/75mm skew nails = 0.66 kN so doesn't meet requirements.
A single framing anchor with 4/2.8 diam nails each side = 3.5 kN therefore OK
The next question is what if you use 4 skew nails ?
And the answer is probably but it's not covered by the framing code that I know of.
At the end of the day if your rafter spans exceed say 2.1 met then I would go for a 'made up' metal side bracket to suit the angle with at least 4 /40mm*2.8 diam to each leg plus skew nailing to initially tie the rafter to the fascia beam.

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## journeyman Mick

I've used custom made metal brackets (6mm thick plate) sitting on top of the hip/valley and extending down onto the tops of the rafters with whopping big coach screws in them. These prevent uplift. The rafter can't drop down because it's supported at its lower end on a pole plate and would need to pivot from the birdsmouth on the pole plate to fall down. As it pivots it effectively grows in length, thus preventing it from falling down. A few 3" nails hold it in place until the steel plate is fixed. 
Mick

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## DvdHntr

> *DvdHntr,*
> If bugle screwing through the end grains is feasable, isn't skew bugle screwing through the side grains also feasable?
> And what gauge would be appropriate for F5 Seasoned TP rafters 190 x 45?

  Yes it is but how are you going to screw into a side grain? Are you referring to skew screwing? I hope not. 
The gauge issue is that from end and edge grains there are limits that apply that are related to gauge (diameter). 
Have you thought of using a ply backing or attaching a second plate to correct the angle.

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## thebuildingsurv

> The beam opposite the house fascia runs along the property perimeter and in some parts along the neighbouring property's garage.

  Now i know u dont have a permit :Biggrin:

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## Dr - 307

DvdHntr, 
I was referring to 'skew' screwing. I take it that that's a big no no! Or not?
Can you better explain the limits associated with gauge and end / side grains.
No, I haven't thought about correcting the back angle as yet but that's a thought although not to keen on that. 
What about on the issue of LVL. Can you notch LVL out. Just a bit so that it sits in and on the ledger. I was looking at my rough drawing and at the wider end of the roof the rafter span will be 5500. 
Here's the area in question.    
Firstly, that roof covering including the window and waist high brick rendered wall is coming down. Looks like it goes into the house roof but I had a very good look and it's attached to the fascia and very cleverly filled and painted to look otherwise. 
The patio area will remain. The deck will start and run over the patio area (2 x 2m) and then come out left as we view past the ferns to the neighbouring garage wall. From there it continues along the wall for about 5m.
The narrow far side span of the roof is 3m. 
The wide span from where the shot was taken is 6m.
Total length approx 8m. 
Yeah I know, 10 degrees my foot. But my concern was fastening the rafters regardless of whether the angle is 10, 15 or 20 degrees. 
I'm now thinking of using LVL for the rafters (at least for the extra long spans) but don't know how they take to notching. I've used hyJoist before to build a single span 4500 x 16000 messanine storage floor but obviously this stuff is different. 
What do you think.........guys??? 
Doc.

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## Dr - 307

> Now i know u dont have a permit

  Nothing a $350 dispensation application wouldn't fix. Asked my brother-in-law if he wanted plans but said........anyway you know what he said. :Biggrin:  
Check out the pics and see what you think. 
Ta,
Doc.

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## DvdHntr

Use the wall plate and the ledger. I would still recommend multigrips to each. I know some people get away with it but the brackets cost very little and the extra insurance is worth it. 
If the span is getting up to 6m then the LVL may be an option, I would check with the HySpan technical brochures as to whether there is any issue with notching in an exterior environment. 
If you are going to skew just skew nail. Skew screwing is possible but you wouldn't want to. Have you thought of running the joists the other way? Have the spans as 4m each side of a centre beam and have end beams. That way the joist spans are shorter and the beams can be larger but less of them. You could use a hiload truss bracket (3 or 4 bolts) directly into the wall and pack out some timber/ply and bolt through the flange for tie down. 3 connections at the wall is easier than 9.

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## Dr - 307

*DvdHntr,* 
I've been thinking about using LVL all weekend or like I said at least for the longer members. I still want the rafters to run conventionally. 
I'll construct it with footings along the fence line (just to keep off the boundary) and I'll go into the ground as opposed to just using post supports on concrete. I'm going to sit the opposing beam on the inside of the posts so we are looking at a straight even surface for a ledger to run along and then use multigrips for the fastening (for the extra insurance) of the rafters to the beam 
I'll ring hySpan and speak to them about notching and spans. For the perimeter I'll use Design-Pine as well as the posts (115 x 115 post size only). This will give me my smooth look and more strength over the F5 TP Dry.
Design-pine I've been told is rated as F7. 
Now, something slightly related (although I feel it will eventually become my best friend) but more to do with tools.
What is the brand of nail gun suitable for j/hangers and the like where it shows the tip of the nail so you can direct the nail exactly through the right hole in the bracket rather than slam straight through the metal and risk tearing it? 
Cheers,
A very sorry and tired Dr - 307 after 2 days in Mt. Martha.  :Cool:  :Cool:  :Cool:  Sunnies are my best friend at the moment.

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## journeyman Mick

> ................What is the brand of nail gun suitable for j/hangers and the like where it shows the tip of the nail so you can direct the nail exactly through the right hole in the bracket rather than slam straight through the metal and risk tearing it?.........

  
Bostitch makes one, (coil nailer) but I'm not sure about the model number. I don't know if anyone else makes one. 
Mick

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## DvdHntr

As a former engineer of Multinail, I know they do not want you to use any nail gun for the very reason you stated.

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## Dr - 307

*DvdHntr,*
Not even the gun with the protruding nail head?
If you're nailing into the hole of the hanger where is the problem?   *journeyman Mick,*
Bostitch? Thanks for the recommendation. I'll look them up. I might even do a tour of the Tool Pages in the forum. 
Dr - 307. :Cool:

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## DvdHntr

I don't know much about the nail gun but I know that many nail guns would damage the plate as they are only thin gauge.

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## Dr - 307

OK, thanks DvdHntr.  I'll keep it in mind.  I know I was reading on the forum about a nail gun that did what I'm wanting.  There was much debate.  I'll find the thread and have another read.
Cheers,
Doc.

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## Dr - 307

Hi guys, 
I thought I would resurect this thread after I took the following pics -     
I guess I'm just reinforcing the fact that many 'cladded' verandahs are being skew nailed rather than being constructed with brackets.  *What are the issues of constructing a roof with this method as opposed to using brackets / multigrips / triplegrips / joist hangers?* 
Thanks in advance,
Dr - 307.

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## journeyman Mick

> ..............*What are the issues of constructing a roof with this method as opposed to using brackets / multigrips / triplegrips / joist hangers?*..........

  No tie down against wind uplift. 
Mick

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## Dr - 307

And that's what the brackets give us right?
So if I was to nail them in with a gun and then multigrip them then that would be more than ample.......right jm? 
Doc.

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## journeyman Mick

Well it would depend on the terrain rating where the structure is located, but in general for non-cyclonic areas it would probably be fine. Up here there's a batten over the verandah beam or wall which gets a 12mm (min) threaded rod through it next to each rafter as additional tie down. Best bet is to work off properly drawn and detailed plans which will give you all that. 
Mick

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## Dr - 307

Thanks for your input jm. 
Doc.

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