Solid Timber floorboards - glueing direct to concrete versus glue/nail to boards

[mcchristof]

Hi all,

I am sourcing quotes for a 28 m2 area that I want to put down solid timber flooring. Ideally interrested in Jarrah, one strip or something as close to as possible and prefer wider planks (but will compromise on thinner if too $). Pre-finished or raw is ok.

During my research for floorboard options, Ive been leaning further away from floating of any kind, and more towards solid timber. Ideally I would like the solid timber blind nailed and glued (currently cement floor under the carpet). But this is proving to be expensive in something like a Jarrah.

I just had a quote from a supplier that has suggested they will GLUE DIRECT TO CEMENT only. Sound great, but upon speaking to other suppliers they do not recommend this direct stick approach and have said that they have had clients years later complain of boards "unsticking" and moving.

Does anyone have any thoughts/experience with this? Ive been quoted $120square metre for 100mm wide solid timber jarrah fully installed, sanded and polished.

Thank you - Chris

[Larry McCully]

Hi chris, I have installed quite afew direct stick floors and found them to be fine. if the other people have been having a problem with boards lifting , then they have noy been using the right glue. Bostic ultraset or Sika T55 is the go. However the best system is to install your floor on battens, 15mm thick is the minimum. To make it even more econominal for you , you may want to consider stripping up some 15mm ply into 50mm wide strips and pin them down at 450 centers. that would be the most cheapest way. the cost of glue is about $8 per sq mt.. in your case $224 worth. you will need 2 sheets 2.4x1.2 at 80 dollors each or so. you will save 100 bucks. you could do all that yourself and get a pro installer and floorsander in to do the rest. this is a better system tan direct stick, but it is fine with limatations. consider ply battens

[mcchristof]

Larry - thanks for your comments. Ive trawled the forum and read a few other experiences with direct stick. From what I can conclude, if possible installing to battens is the preferred method. The thing is, when you hear a few bad stories about a particular method, one becomes cautious of that method. I wont be doing any of the work, but will be contracting to a supplier to do entire job

Ive also just been reading about the Boral slimwood overlay flooring system. Im not clear on how these are any different to planks of solid hardwood timber, except they place these as floating rather than bearer and joists to a sub-floor structure. Any thoughts? Seem marginally better than Boral's silkwood which are basically just 4mm of hardwood on pine base/core.

Thanks Chris

Hi chris, I have installed quite afew direct stick floors and found them to be fine. if the other people have been having a problem with boards lifting , then they have noy been using the right glue. Bostic ultraset or Sika T55 is the go. However the best system is to install your floor on battens, 15mm thick is the minimum. To make it even more econominal for you , you may want to consider stripping up some 15mm ply into 50mm wide strips and pin them down at 450 centers. that would be the most cheapest way. the cost of glue is about $8 per sq mt.. in your case $224 worth. you will need 2 sheets 2.4x1.2 at 80 dollors each or so. you will save 100 bucks. you could do all that yourself and get a pro installer and floorsander in to do the rest. this is a better system tan direct stick, but it is fine with limatations. consider ply battens

[Toymaker Len]

I did a bluegum direct stick to concrete floor a few years ago with the bostik glue. Had to go direct stick for the ceiling height as it was right on the minimum. Also used a bostik concrete sealer first. So far it looks good and no movement. The main advantage of solid timber that I see is that you are able to resand and refinish the floor quite a few times unlike the very thin floating floors. The main disadvantage of the direct stick method is that our bluegum floor is cold and hard like the concrete which it is stuck to rather than being warm and slightly giving. $100 per metre square sounds pretty good but get a few quotes before you decide.