Wooden Floorboard project

[dojo]

Just found under the grotty carpet in the front room there look to be some very dirty but potentially nice floorboards.

The idea would be sand back, put pine slivers in the gaps and then varnish.

One corner has dropped away so need to lift those boards to look at joists underneath.

Obviously I'm keen to reduce heating bills as much as possible but on the other hand I don't want to create a shed load of extra work and expense!

Question is will the slivers do the job keeping the heat in or will there be a massive difference if I lift all the boards and put down some insulation materials??

Think its going to be the former, but no pointing in half doing a job... just makes it quite a lot more of an ordeal (and a lot more earache!!!)

[Paul Drawmer]

Putting a new pine infill piece in between each board will be an arse of a job without lifting every board.

Therefore; as it's easier anyway, pull up all the floor, check and treat all the joists, insulate and re-lay floor. It will be a better job and quicker than trying to fit every infill piece. You can think about using contrast strips, or just butt all the old boards up and add one or two new at the side.

[dojo]

Hi Paul,

Thanks for the reply. I was under the impression you could buy wedge shaped bits of pine and drive them down into the gaps, let them set, chisel off the excess and sand down when you do the floor? I will happily (well not happily) lift all the boards if needed but if difference is marginal I might not bother

I know its sales blurb but this is what i was looking at.

http://oldpinecompany.co.uk/acatalog/About_Old_Pin...

Thanks

[Simpo Two]

Quite a nice idea I think - as long as you don't dig into the grain when levelling and get a hollow/damaged bit.

[smn159]

I pulled my floorboards up and put Celotex between the joists when I did mine. Wasn't a bad job and the insulation does make a noticeable difference.

Gives you a chance to inspect the joists as well

[GreenDog]

I thought most people just made up a filler with some sawdust they'd sanded off and some glue and filled the gaps with that and sanded the top again to smooth it once dried.

[AlexJ12]

dojo said:

Just found under the grotty carpet in the front room there look to be some very dirty but potentially nice floorboards.

The idea would be sand back, put pine slivers in the gaps and then varnish.

One corner has dropped away so need to lift those boards to look at joists underneath.

Obviously I'm keen to reduce heating bills as much as possible but on the other hand I don't want to create a shed load of extra work and expense!

Question is will the slivers do the job keeping the heat in or will there be a massive difference if I lift all the boards and put down some insulation materials??

Think its going to be the former, but no pointing in half doing a job... just makes it quite a lot more of an ordeal (and a lot more earache!!!)

Pine Slivers do work, but as someone else pointed out there is no easy way of doing them. I charge double for this over a Mass Fill.

Mass Fill (filling the gaps between the boards) is the easier route if you are sanding the floor but it needs to be minimum 80 or 100 grit dust for it to work properly. I double fill on every job, first is a thicker one and then a sloppier one just level it out properly then sand it back again to get the excess of the rest off the boards. It will over time crumble out if the boards are not secured properly and if the boards are to close together it wont take filling properly and again pop out over time. The best filler I am using at the moment is from company called Blanchon, it goes off really quickly and is rock hard.

If you are thinking about doing it yourself I can give you as much as fine dust as you like, I dump maybe 5 or 6 bags of it a week.

If I were you I would use Celotex and or buy some decent insulation for under the boards.

Or look at it a different way, is there a big rug going in the room and sofa's? If the answers yes then 2/3 of the floor are going to be covered anyway...

[Yazar]

dojo said:

Question is will the slivers do the job keeping the heat in or will there be a massive difference if I lift all the boards and put down some insulation materials??

If you take up the nailed boards, chances are you will cause a bit of damage to them, so take care. If you are going to do it, since its the main living room, well worth both insulating and adding underfloor heating.

Insulation- if a flat with neighbours below then use 100mm mineral wool (will reduce sound), if house then Celotex-type is thinner and more efficient.

Edited by Yazar on Saturday 22 November 11:01

[dojo]

Thanks for the answers guys, I'll drop you line Alex if I go down the mass fill route. Think I'm going to start off by repairing the dropped corner and giving it a provisional sand to get an idea, then decide whether to go the whole hog or re carpet...

[dojo]

It looks as if I am going to have to take a chunk of the boards up to fix some of the joists...
Therefore going to go whole hog and celotex insulation under the boards... Does anyone have any recommendations as to the best or which celotex thickness I should use??
Thanks

[Gtom]

Last time l looked at the regs it was 80mm of celotex for a floor, it may be more. Set some tile lath down the thickness of whatever you put in for the insulation to sit on and seal every gap with expanding foam. Cover all joints with silver foil tape then lay a thin plastic membrane over it all before laying the floor back down.

Also take some photos of this and you can show them to the person who does the EPC when it comes to selling. Or get the council to inspect but this is a extra cost.

[dxg]

Go one step further and lap and tape the joints in the membrane and then tape the membrane to the plaster at the perimeter using some air-tightness tape (e.g. http://www.greenbuildingstore.co.uk/page--pro-clim... Then replace the skirtings over the tape.

[dojo]

Started this a couple of days ago, had to rebuild the footings, all celotex is down and boards back in situ... In the middle of nailing boards back down which is a killer! Hey ho. Sander is hired and all going well should be up and running tomorrow.

[guindilias]

When I bought my 1967 built semi 10 years ago, I ripped up the 1970 style carpets and saw that the boards were all chopped when the central heating was bodged in. Decided to bin the boards, and stick in brand new ones, all butted up tight, glued, and then varnished with Diamond coat varnish.
The worst thing I ever did in this house was to not even think about putting in some insulation underneath, and a membrane.
That, and hammering in 700 floor brads by hand. Even my legs hurt after doing that, and I don't hammer with my legs!
The floor is constantly cold, and I am going to rip the whole bloody lot out and INSULATE, then spend a small fortune again on new boards and varnish. I honestly think it'll recoup the costs in about 2 years just through reduced heating bills!

dxg said:

Go one step further and lap and tape the joints in the membrane and then tape the membrane to the plaster at the perimeter using some air-tightness tape (e.g. http://www.greenbuildingstore.co.uk/page--pro-clim... Then replace the skirtings over the tape.

[okgo]

15 months ago I did my floors. I had big gaps. I used both saw dust and pva and pine slivers.

In high traffic areas the pva stuff is already falling apart. The slivers still going strong. However they will come lose unless you use a few layers of varnish I think. Just standing on the board in the wrong way will crack the bond between the board and the sliver.

It's probably now time for me to slap another layer of gloss varnish down but I can't be arsed with the hassle of sanding again. Wondered if I cleaned the boards down and applied the varnish I might get away with it...

[wolfracesonic]

Can I ask OP why the insulation doesn't come to the top of the joists and hit the underside of the boards, or is there another layer of insulation/UFH to go in I'm not seeing?

[dojo]

wolfracesonic said:

Can I ask OP why the insulation doesn't come to the top of the joists and hit the underside of the boards, or is there another layer of insulation/UFH to go in I'm not seeing?

I left a little gap cause 1.it was easier to put a batton underneath the joists to support the celotex and 2. I'd there were any small gaps gown the side of the celotex I could fill with expanding foam. The whole thing is draft proof and there is enough room underneath for ventilation via the airbricks so should be good.

[Hash1988]

I did my kitchen floors about 6 months ago. Filled all the gaps in with 2part resin then sanded whole floor after gives a dark line like the natural gap it did have before, then used Matt marine varnish, ment I can mop it as well. Only wish had pulled up more boards like your doing and insulated as have a 2 foot drop under.

[Jimmyarm]

How do floorboards resist woods natural tendency to expand/shrink with temperature and humidity fluctuations ?

Always thought the gaps were there to account for this but every one seems to fill them in =)

[TA14]

Jimmyarm said:

How do floorboards resist woods natural tendency to expand/shrink with temperature and humidity fluctuations ?

Always thought the gaps were there to account for this but every one seems to fill them in =)

In most houses floorboards just shrink. When they are put in they are put in under pressure http://www.tradetoolshop.com/faithfull-flooring-cl... with no gaps but the moisture content in the wood is higher than that of the finished house so they shrink and shrink. People who fill in the gaps with slivers have them become loose because the floorboards shrink more but you don't get buckling due to expansion. One advantage of chipboard flooring I suppose.