Draught from beneath old floorboards

Boorad · 7 Nov 2003

We recently bought an old victorian house with high ceilings and big bay windows. The missus was keen to rip up the carpet and sand the old floorboards down. A few of my friends had done this and warned me of the draught that they constantly experienced from under the floor and the rooms were alwasy cold. The old floorboards are suspended with about 2 foot of space to the solid floor below. Anyhows, I went along with the wife, we hired out a sander, sanded the floors and then varnished. We are now constantly wrapped up in blankets even though there is a rad in the room, I can put my hand down and feel the draught and cold air coming through between the florrboards.

How do I fix this problem? I can try and fill the gaps between the floorboards but this could be costly and alot of work? Someone suggested taking the floorboards up and putting roofing felt down and then replacing the floorboards. Or do I just overlay floor with new hardwood flooring.

Please help as it is getting colder everyday!

loftus75 · 7 Nov 2003

Your experience is probably the same as many others that have watched TV programs that suggest this, not only can it cause drafts but it wis likely to increase the dust one finds in the room.

There are somethings you might try.

You could fill the gaps with a string type material, this is where the term caulking really came from as it was used on ships that had wood planks, apparently you can still get the stuff from some marine suppliers. However, I doubt it will be as attractive as your wife would like. Neither would it give you a long term solution unless you intend to keep the floor damp as the floor will always loose a lot of humidity in the winter and the boards will shrink when the central heating is turned on.

You could forget the real wood idea, and lay a laminate or veneer floor with a thermal underlay. This would be my first choice as it solves your problems and offers your wife the look of a wood floor.

The one thing you should not do is try to seal up the air bricks that are the reason for you draft as you will create a more serious problem with damp under the floor.

Sorry I can't be more helpfull then this.

Boorad · 7 Nov 2003

Thanks for the advice. I am new to the wood flooring idea, i have seen laminate and know you can get 'real' wood flooring aswell. You mention thermal underlay? is that something i can get from the likes of B&Q?

masona · 7 Nov 2003

Thermal underlay is what you put under laminated floating floor.

There are professional company who specialise in filling floorboards joints with string type material as loftus75 said,but they have to completed the job for you including straining as it require difference type of materials.A friend of mine had it done and cost approx £400 on floor size 17' x 13' couple of years ago.I don't know what the long term problem are if any.

Just a thought,

Can you not lift some floorboards in the corner and get a smaller person underneath to insulated between the floor joists as you have 2' clearance?

A good investment would be to rip out old floorboards & put in insulation slabs or roll insulation between floor joists and renew with T&G floorboards.My floorboards is always warm even without the heating!

Wickes do a nice woodgrains 22mm T&G called Bordeaux flooring with a hint of red grains and you can secret nail them

Porker · 7 Nov 2003

I would go with the slab insulation fitted between the boards. My uncle has just replaced his boards with oak and put the insulation in. Looks great and no draughts.

kostello · 8 Nov 2003

or you could do what i did.

take all the boards up lay chipboard t+g floorong then refit the boards and sand and stain

aleks

Boorad · 10 Nov 2003

Guys,

apologies for lack of knowledge but does T&G stand for 'tongue and groove'?

Thanks

pb21 · 10 Nov 2003

I just did this, remove the floorboards, then as the others guys say get 18mm tongued and grooved chipboard approx £5 per 2.4 mtr length so its not expensive. then buy the laminated floor underlay which is £20 per 10 sq mtrs so not too bad, then buy a nice laminate but AC3 grade B&q have an offer at the moment on this at about £7 per sq mtr and go for a darker colour perhaps cherry.

its all easy to lay just leave an expansion gap of 10mm around the edges. I would go under the skirting if you can but fix the skirting very slightly above the laminate so it can expand and contract.

Then you will have a warm house and as the other chap said dont block the air vents.

masona · 10 Nov 2003

Boorad said:
apologies for lack of knowledge but does T&G stand for 'tongue and groove'?

Yes,but also not Transport & General union

DavidH · 18 Nov 2003

It seems a shame to rip up and replace the flooring if its in good nick and has a nice aged look. You will inevitably loose a few if you pull the whole lot up no matter how careful you are.

I liked the idea of lifting a few in the corner and insulating from underneath. Although not as good as insulation, tacking hardboard to the bottom of the floorboards will stop the drafts.

Could always get a few rugs

Mainmaintenanceman · 2 Dec 2003

I had just this problem under identical circumstances. I bought some kingspan insulation, cut it to the width between the joists and put it in from underneath. Tape up the joints with duct tape. Its not easy on your back with just 2 feet of headroom but it has cured my problems. Just make sure it is a good fit between the joists.

miah · 10 Dec 2003

Hi All,

Need your opinion on this please.

We are in the process of putting new radiators in the house which means there will be a lot of floor boards lifts and shifts so probably this is our chance to insulate the floor and replace it etc....

We are thinking of laying laminate floor, as for insulation process, how do I put insulation near the joist?

And why do I have to insulate the joist for?

Finally, shall we replace the entire floor board? and the moment there are some minor crack's etc...and I’m thinking when we fit the rad's the floor will be quite damage.

I read some post suggesting chip –board, if so, what would be the correct size thickness etc... will this board last for long for time?

Appreciate your help.

masona · 10 Dec 2003

miah said:
We are thinking of laying laminate floor, as for insulation process, how do I put insulation near the joist? And why do I have to insulate the joist for?

You don't have to,if you haven't got T&G flooring then it can be quite draughty but not with underlay + carpet.If you're going to have laminated flooring then they will come with insulation underneath which it's just as good.It will be a lot more warmer with the insulation between joists as a bonus.If you want to put in insulation then the only way is to rip out all the old floorings.

Finally, shall we replace the entire floor board? and the moment there are some minor crack's etc...and I’m thinking when we fit the rad's the floor will be quite damage.

You can decide that afterward

I read some post suggesting chip –board, if so, what would be the correct size thickness etc... will this board last for long for time?

Yes,the T&G chipboard come at 18mm thickness.

miah · 10 Dec 2003

Thanks Masona.