fixing solid oak flooring to concrete base

[rowntree20 1]

I am planning to fix solid oak flooring to a concrete base using Sika T55 from Topps tiles. does anyone know if this is really suitable and if it is easy to use. thanks

[Rich 2]

Hiya Rowntree

Sticking wood to concrete with any adhesive is always going to be a bad idea because wood needs to breath and it moves (Expension/contraction) which you really dont want if you stick it down because if the adhesive wont give, then the wood will.

The best thing to do with any wooden floor is either nail/screw it down, or leave it as a floating floor using a top quality underlay.

I've laid Oak flooring in my place and the underlay I used is absolutely fantastic, I got it from wood4floors.co.uk and its 4mm thick, silver lining on the back of it and insulates both temperature and noise (28db)

So something like that would be far better as you can then also ensure that you keep the oak flooring at a reasonable tempurature with less variation to distort it, but ensure you leave at least a 8-12mm gap around the edges of the walls so that the entire floor can expand/contract without forcing itself up off the floor...

Why not show us a picture of the area your planning to work on?

[woodman2008 1]

Dear Mr DIY Guy you need more experience and expertise before answering questions like this.

It is widely accepted practice in the UK to use flexible adhesive to bond solid wood flooring to solid substrates like Concrete/screeds.

the underlay that you used is useless when fixing solid wood flooring and it is against best practice to float a solid wood floor as this leads to failure in the bond and eventual separation of the flooring. This may of course take some time but in the end it will happen.

it is a good idea to keep the ambient temerature stable but the use of underlay will nothelp this in any significant way. Wood itself is a good insulator and cold wil not be felt coming up from the substrate.

if you have installed a solid wood floor floating on underlay why don't you show us a picture now and then again in a year or two. should be interesting.

Anyway Rowntree to answer your question:

Sika T55 is not a very smart solution. Although it is not mentioned when you buy this product I would suggestbthat you take a look at the following URL which provides interesting reading on Sika T55. You will see that it is not a particularly safe product to have your face over for a few hours and I can't believe that this is sold to the public without any warning.

http://www.merciaflooring.co.uk/sikat55.pdf (see page 2)

With regard to your other answer where you have been advised that Sika is the 'next generation of flexible adhesives' this is incorrect. Sika is a polyurethane product as is Mapei 990K and this technology is definately not new. The latest generation of wood flooring adhesives is MS based products which unlike Sika and similar do not contain hazardous substances. I am surprised that you are being advised to use Plyurethane products which carry warning labels on the containers are difficult to use and generally leave you with a difficult clean up job.

[Rich 2]

Dear Mr DIY Guy you need more experience and expertise before answering questions like this.

Whis is why I'm glad you joined

It is widely accepted practice in the UK to use flexible adhesive to bond solid wood flooring to solid substrates like Concrete/screeds.

the underlay that you used is useless when fixing solid wood flooring and it is against best practice to float a solid wood floor as this leads to failure in the bond and eventual separation of the flooring. This may of course take some time but in the end it will happen.

Hey, were not all perfect, and lookig back, I do believe I missed the "Solid" part and just read "oak flooring"

I myself laid Engineered oak flooring which lock's together and is actually designed to be a floating floor and was laid on newly laid plywood flooring over 18 months ago, and its still as good as new...

it is a good idea to keep the ambient temerature stable but the use of underlay will nothelp this in any significant way. Wood itself is a good insulator and cold wil not be felt coming up from the substrate.

Indeed, ambient temperatures should always be kept stable, but underlay (A damn good quality one, not that cheap foam crap found in homebase/B&Q) will actually help.

if you have installed a solid wood floor floating on underlay why don't you show us a picture now and then again in a year or two. should be interesting.

Not really, its fairly boring, the floor looks exactly as it did 18 months and is still in great shape, and will be for many many years to come.

The underlay I used is fixed down to the plywood, and the ply backing on the engineered planks actually grip the underlay, so although the flooring isnt physically fixed to anything, it doesnt move around at all.

If I still live here in another 18 months, I'll be happy to report back on how its doing, but having seen another install of the same product, done 5+ years ago, I know what it will look like..

Thanks for the good info to Rowntree too