Engineered wood floor instal

[Dylan123]

Hi,

Looking to floor the bottom floor of my house in engineered wood. I am thoroughly, thoroughly confused on how to do this. I’ve just read 4 articles which contradict each other entirely!

the job:

- 1939 terrace. Lare crawl space below which is dry as a bone.
- floorboards are in good condition, some high and low spots but boards aren’t noticeably damaged or cupped.
- i have a hallway (approx 5m2) which joins into the dining room and living room. I plan to threshold separate this under the doors.

- the dining room and living room are one big room with a connecting double doorway (I removed the interior doors)
- the run from the dining room through to the living room is about 7.6M. I would prefer to not break the floor under the (now removed) double doorway.
- the width of both rooms is about 3.3m.
- the long run (7.6m) is roughly east to west so the sun is running that way.
- I want the boards to run the same way (ie along the long run rather than side to side along the 3.3m)
- the existing floorboards run this direction too.

I initially considered buying 20mm engineered and going straight onto the floorboards but felt this was asking for trouble as the floor will be running the same way as the floorboards. Also I just feel straight onto the floorboards isn’t a good idea. Also 20mm is darn expensive.

So I then decided to lay 6mm exterior ply over the floorboards and probably a 14mm engineered wood T+G.

now this is where it gets tricky. Some articles say that 7.6m run is a bad idea for nailed/glued and floating is better. Others say you need loads of threshold expansion gaps for floating (so the 7.6m run would need a break under the old door space)

so I then thought ply subfloor and nailing the engineered wood.

I then saw articles claiming you never nail unless it’s 20mm hardwood.

most are saying glueing is mainly for concrete subfloor

I don’t care either way, I’ve done a floating floor before but happy to buy a nail gun. I just want a floor which won’t be buckling etc for years to come.

so come on, what do I need to be doing here?!

Thanks in advance for your help!

 

[dontbelieveawordofit]

engineered t&g floating , glued .
why the ply?
it’ll only ‘buckle’ if you have seriously excessive variations in humidity.
leave big enough gaps for expansion around the edges and engineered wood is forgiving enough for a 7m run.
but stick to thresholds at the doorways.
be sure to use the dearest recommended underlay they recommend and you can afford.
being as no dedicated floorists came along

 

[Deleted member 174758]

engineered t&g floating , glued .
why the ply?

Because the OP wants to run the engineered flooring in the same direction as the original planked flooring. You normally run either at right angles or diagonally to the underlying flooring. I have to admit , though, that I've never nailed flooring thinner than about 20mm, either.

Not a "floorist" either, but done some solid hardwood flooring, laminate, parquet over the years as well as a lot of sub-floor prep (coz I'm a "wood butcher"). Hopefully someone like dazlight will be able to enlighten us

 

[crazydaze]

Depends on the quality of the Engineered product if it can be nailed/glued or has to be floated rather than the thickness.

If you want to nail it, them 9mm Flooring Grade ply and prep would be ideal.

If floating that one space should be fine without a break, I would use Duralay Multitex underlay, floated will have less potential issues and the underlay will be insulating and slightly more comfortable than ply and pin.

High Quality Floors like V4 Engineered flooring you can pin the 15mm product no problem.

A Laquered finish is highly resistant to marks, dirt build up and is wipe cleanable. UV Oiled would be a true surface with some decent protection from spills, an Oiled or Waxed finish will be a nightmare to keep looking nice and very susceptable to water marks from spills etc.

 

[Dylan123]

Depends on the quality of the Engineered product if it can be nailed/glued or has to be floated rather than the thickness.

If you want to nail it, them 9mm Flooring Grade ply and prep would be ideal.

If floating that one space should be fine without a break, I would use Duralay Multitex underlay, floated will have less potential issues and the underlay will be insulating and slightly more comfortable than ply and pin.

High Quality Floors like V4 Engineered flooring you can pin the 15mm product no problem.

A Laquered finish is highly resistant to marks, dirt build up and is wipe cleanable. UV Oiled would be a true surface with some decent protection from spills, an Oiled or Waxed finish will be a nightmare to keep looking nice and very susceptable to water marks from spills etc.

Are you saying I don’t need ply if I float and use underlay? I thought it literally had to be like a billiard table regardless of what method.

I read if you lay a 2M straight edge you shouldn’t be able to slid a £1 under it. My floorboards are pretty good but I doubt they are that level. I definitely have one raised joist by say 10mm....can plane the boards, but I thought ply was non-negotiable if you want no trouble with the floor on top.

I was going to lay 14-15mm t and g and 6mm ply. I could just buy 20mm if I don’t need ply. Also as the other poster says, I want to go the same way as a floorboards.

although it’s a 7m run, I have a large doorway along that 7m. A lot of guides say expansion gap under any doorway. This isn’t a single doorway, but just the hold from where a double doorway wAs. See pic

can I float this whole space and not leave expansion at the “hole”?

I’ll def spend the money on underlay, but a friend of mine who’s a builder said he always uses ply underneath as had problems when he didn’t.

I successfully levelled, boarded and laid LVT planks in my bathroom so I felt this job wasn’t beyond me for DIY. I wonder if it’s worth paying the extra £900 for the fitting.....I thought laying floor wasn’t that difficult provided it’s done right.

 

[crazydaze]

Are you saying I don’t need ply if I float and use underlay? I thought it literally had to be like a billiard table regardless of what method.

I read if you lay a 2M straight edge you shouldn’t be able to slid a £1 under it. My floorboards are pretty good but I doubt they are that level. I definitely have one raised joist by say 10mm....can plane the boards, but I thought ply was non-negotiable if you want no trouble with the floor on top.

I was going to lay 14-15mm t and g and 6mm ply. I could just buy 20mm if I don’t need ply. Also as the other poster says, I want to go the same way as a floorboards.

although it’s a 7m run, I have a large doorway along that 7m. A lot of guides say expansion gap under any doorway. This isn’t a single doorway, but just the hold from where a double doorway wAs. See pic

can I float this whole space and not leave expansion at the “hole”?

I’ll def spend the money on underlay, but a friend of mine who’s a builder said he always uses ply underneath as had problems when he didn’t.

I successfully levelled, boarded and laid LVT planks in my bathroom so I felt this job wasn’t beyond me for DIY. I wonder if it’s worth paying the extra £900 for the fitting.....I thought laying floor wasn’t that difficult provided it’s done right.

It's hard to comment without seeing the floor but first you say it's level and now there in a 10mm difference in one area?

The floor needs to be level, but it doesn't need to be billiard table smooth if you are floating it. Even plying the floor may not give you a billiard table smooth floor especially if you have a area with 10mm ridge.

The flooring itself needs to be designedd for fixed installation, if it is not, and many engineered floors are only suitable for floated installation, then floating may be the only option any way.

In my experience, builders aren't quite the trade to advise on professional engineered wood flooring installation, we are in the process of putting right £15k's worth of 'my mates a builder he said it would be fine' for a customer.

Maybe get a local independent specialist flooring shop in to advise on-site regarding the product and levels.

 

[Dylan123]

It's hard to comment without seeing the floor but first you say it's level and now there in a 10mm difference in one area?

The floor needs to be level, but it doesn't need to be billiard table smooth if you are floating it. Even plying the floor may not give you a billiard table smooth floor especially if you have a area with 10mm ridge.

The flooring itself needs to be designedd for fixed installation, if it is not, and many engineered floors are only suitable for floated installation, then floating may be the only option any way.

In my experience, builders aren't quite the trade to advise on professional engineered wood flooring installation, we are in the process of putting right £15k's worth of 'my mates a builder he said it would be fine' for a customer.

Maybe get a local independent specialist flooring shop in to advise on-site regarding the product and levels.

thanks.

I have carpet and laid a 1.5m level over the whole floor and the whole thing is dead level except one joist which seems to be high. Maybe not 10mm but the level suggests it’s definitely a ridge, but feel this could be sanded out.

just one other thing, it wasn’t clear from previous. I want to run the same way as the board.

does this make boarding over in ply essential, or would a really good underlay suffice?

I am planning on spending a lot of time getting the boards level and properly nailed down first. I’m wondering if ply is essential if going the same way as boards.

many thanks

 

[crazydaze]

thanks.

I have carpet and laid a 1.5m level over the whole floor and the whole thing is dead level except one joist which seems to be high. Maybe not 10mm but the level suggests it’s definitely a ridge, but feel this could be sanded out.

just one other thing, it wasn’t clear from previous. I want to run the same way as the board.

does this make boarding over in ply essential, or would a really good underlay suffice?

I am planning on spending a lot of time getting the boards level and properly nailed down first. I’m wondering if ply is essential if going the same way as boards.

many thanks

If you can get that joist area level with the rest you will be fine to lay on a good quality underlay like Duralay Multitex.

If you are in the position to ply the floor, then for ‘belt and braces’ the finish will ultimately be that little bit better but from what you describe, not essential.