# Forum Home Renovation Flooring  New floor boards over existing ones

## ptt102

Hi, 
After reading the relevant threads on this forum and the flooring manual from www.timber.org.au, I still have questions about laying new floor boards over the existing one. Before I ask the questions, here is the situation. 
The original house was extended ages ago and as a consequence about 70% of the floor boards are 85mm wide and the rest 130mm or so. During the existing renovation few wall have been moved around, leaving openings in the floor. The openings can be patched, but the floor will look patched. One patch may be tolerated, but there would be quite a few of them, so that is not an option.  
The remaining two options are to replace the existing floor boards with new ones or to lay the new floor borads over the existing ones.I prefer the second one.  I'd like to lay 85mm x 19mm Tasmanian Oak over the existing hardwood floor. 
The plan is to check the condition of each of the existing floor boards and put a screw or two where required to make it nice and solid. 
The next step would be to rough sand the floor and when it's all clean re-check again if it is level. So far so good. 
As for the following step, I am not sure which way to go. 
The flooring manual basically says the boards can be laid either perpendicular to the existing ones (if they are solid and sound) or parallel to them. If they are laid parallel, the middle of the new borads should overlap the joints of the old ones. There is no mention of plywood underlays. 
On the other side, there is the advice to lay playwood underlay before the new floor boards. And there is some debate whether it should be 4mm or 12mm.  
I am really confused and don't know what is the right way to go. Can someone shed more light on the situation?
I really need to know if underlay is required or not and if it is required, what material to use and how to install it.  
Thanks in advance,
ptt102

----------


## dazzler

I would pull em up and relay them.  This way your not lifting the height of your floor which may bring problems with door gaps if they are in the way and /or transitions into other areas it wont be a problem. 
If you pull em up you can then adjust your bearers/joists for height and restump if required.  You also wont have the problem of wood movement in different directions and gaps between the two boards. 
You will also save a heap of money!

----------


## ptt102

The restumping was done already and all doorways and doors are new, so neither is an issue. 
Is the extra work of pulling the old boards out justified? Is the end result noticeably different? I am really pressed for time to finish the renovation and wouldn't like to stretch it further unless it's absolutely necessary. 
Besides, I had impression that the extra support of the old boards will make the floor more solid.

----------


## UteMad

If you go over the top make Bostich ultraset your best friend to avoid getting squeaks between the two.. we went perpendiculay and larry mccully sanded it ..  
cheers utemad

----------


## Dusty

Just simply fix it.  
The best bet would be to fix the patches in a such a way that it (almost) becomes invisible. It's not that hard & in most cases works out less expensive than replacing, or, in your case, re-laying an entire floor. 
Pretty much nothing in the way of flooring is un-repairable. 
Here are some links to repair work I've performed on various floors. Maybe that's the sort of thing that might fix your problem.  Repair number 1 
Repair number two  Repair number 3  Repair number four

----------


## Bloss

I'd put the new boards on top and as UteMad says make sure they are glued and nailed. If you run them the same way as  the existing flooring you can nail into the existing joists. It will work either way, I just prefer to run them the same direction. The occasional overlapping join is not an issue but good practice to try to have the new joins not aligning over the old. I've juts covered  a hallway and a family room radiata floor with 19mm brushbox. I have a Fein Multimaster so trimming the door jambs etc was easy and the family room floor was where and three extensions met badly and unevenly (not done by me!) with height differences of 10mm or so in 3 directions in a 5mx4m room! Took some levelling using planing on high spots and shaved & shaped masonite packers on the low. Plenty of glue and secret nailed - it has come up a treat. 
The again you are in Melbourne - talk to Dusty . . .

----------


## dazzler

Maybe I am missing something here but why are we covering an entire timber floor with another one when the other one can simply be repaired? 
No old timber floor is dead level so when you lay the new one you are going to  have voids between them. The new floor copies the old floors problems.  If we are going to fit a complete new floor then why not just pull up the old one, save the good boards and relay it (or put nice new ones in) on a level, properly stump repaired substructure. 
I can see a benefit if you are a contractor and want to get in quick and get it done (at a cheaper price for the customer I would also guess) but for the DIYer doing it this way seems much more expensive. 
So what am I missing?

----------


## pawnhead

Some nice repair work there Dusty. I was going to suggest the same. 
That's a great looking finish on that floor Bloss. A hell of a lot better than the crappy job I did myself out the back here.  :Redface:

----------


## ptt102

In principle I don't have a problem with repairing the floor, but there are a couple of issues. 
The floor boards width is not the same and the two different widths meet almost in the middle of the living room. 
Also the house was built when floor boards were just something to walk on. I suppose no one cared about their appearance because they were covered with carpet. If I keep them, they won't be aesthetically  most appealing.   
Few new doors were already installed as if new boards will be laid over the old ones. One I can't move as it is in the bathroom and it's all tiled already. 
I was also keen on the finish the secret nailing gives me. 
As much as I can see Dazzler's point I may have to continue in the direction I was going. I wish I stumbled across this forum earlier. 
Bloss, did you put anything between the old and the new boards?

----------


## Dan574

Post some pics and let the wealth of knowledge tell you what can be done.  as they say a picture tells a thousand words and in this case may save you some dollars as well.

----------


## ptt102

Good idea, I'll do that. There are quite afew photos to take, but I'll do my best. 
As I was thinking about the best way to photograph as many of the areas of concern as possible, I realised that in one of the hallways there is a patch of exposed concret. From memory it is about 100mm x 500mm in size. 
It's part of a larger slab, the majority of which luckily remains in the second bathroom and the toilet so it will be tiled over. The plan with the exposed bit was to cover it with new floor boards. I don't think it could be done if I keep the existing ones. 
I'll post the images anyway and wait for some feedback. In the mean time any ideas are welcome.

----------


## leeton

Nice work Dusty...just a question...what is the secret of staggering new boards into the old...I only have a small area to do...but find getting a new board in between the old without damaging both...mine are pretty tight.

----------


## Dusty

Thanks for the kind words, Leeton (& John) 
I've quickly put together a couple of pictures showing a basic repair job. It may be of some help in showing you how to get them in without too much drama.  http://picasaweb.google.com/clintfud...eat=directlink 
Hope it helps
Got any further questions, just ask. :Smilie:

----------


## Gaza

Nice job dusty, 
hope you have a multi master to do the end cuts. 
P.S your van is in the photos but is not lowered like the picture.

----------


## leeton

Thanks Dusty...makes sense now...I will fix the floor with confidence now. :2thumbsup:

----------


## Dusty

> Nice job dusty, 
> hope you have a multi master to do the end cuts. 
> P.S your van is in the photos but is not lowered like the picture.

  Once had a Multi-master and some @@@@ stole it from a job site. I simply just cut the ends with a power saw, then chisel out the remainder. 
That's the same van that's in my avatar, but the one in the avatar has been photo shopped by one of our woodwork forum members Harry72. He did a grouse job.

----------


## dazzler

> I 
> As much as I can see Dazzler's point I may have to continue in the direction I was going. I wish I stumbled across this forum earlier.

  Hey 
Not saying its the wrong approach by any stretch. Just interested in why is all. 
Best of luck.  Dont forget pics :2thumbsup:

----------


## ptt102

Here are the photos. What is the verdict?  :Smilie:  
What I really want to work out at the moment is the long term difference between the quality of new boards laid over the existing floor, versus re-laid from scratch, versus repaired. As long as I can work out what quality of finish and durability I can expect from each of the solutions, I should be able to decide which way to go. 
Then there may be some tachnical questions, but that's the easy part.  :Smilie:

----------


## ptt102

... and two more photos that didn't fit with the previous post.

----------


## pawnhead

That looks like a similar situation as I've got with my concrete, but I've had no expert opinions yet.
Perhaps I shouldn't have babbled on so much in my description, tl,dr.  :Redface:

----------


## Dan574

Get dusty in there to work his magic, his repair jobs look awesome.

----------


## ptt102

Dusty's work looks really amazing, but that would take the fun out of DIY. 
By the way, any wisdom on the original question?

----------

