Dipped Floorboards

Captain Kidd

Hi, recently bought a house, and some of the floorboards are dipped below the skirting. I’m guessing this is to do with them drying out? It’s an early 1900’s house. Any idea how difficult this might be something to fix? I’m almost scared to ask! I would rather not replace.

Thanks for any help worth this.

Stone Deaf 4evr

I'm not sure whats going on in that last picture, it looks like the wall over the skirting was replastered down on top of it.

Anyway, to the the issue at hand, The gap looks to be too big to apply a bead of caulk along it without it looking awful, and moreso given the floorboards themselves are likely going to have a lot of variation in them, making it difficult to get a clean line.

perhaps look at adding some additional trim along the bottom? something like this (but in white)

https://www.diy.ie/departments/primed-white-pine-scotia-softwood-moulding-l-2-4m-w-23mm-t-23mm-0-53kg/1821953_BQ.prd

tom1ie

Scotia is your only man.

Captain Kidd

Thanks both, will look into this 👍🏼

10-10-20

I'd have a carpenter come in and remove and refit the existing skirting and refill and repaint them. He should be leaving a very small gap of ~3mm and then caulking the gap to close it. If it's the same downstairs, consider having the floorboards lifted and refitted with insulation between the joists before refitting the skirting (if you have no suitable insulation in place).

C. Eastwood

The gap is probably caused by the drying out of the flooring joists which caused the tongued & grooves flooring deck to drop a few mm.

Similarly if the skirting boards are fixed with nails at the centre or top, (which is standard) when the timber moisture content of the timber dries down a few %, it causes shrinkage, and therefore the height of the boards to reduce and the bottom of the boards move up a few mm.

This happens in most houses because the timber is not at the correct moisture content when fixed in place.

The correct Moisture Content is approx 12 to 14 %

Don’t do anything with the skirting boards or T&G flooring.

Fill the gap between the t&g flooring boards and the bottom of the skirting boards, with silicone mastic if there is a draught at that junction, and paint over same.

If there is no draught, fill the gap with painters caulk and paint over.

This will give you a very good cheap solution for the present.

In the future if you decide to replace the skirting boards, you can retain a Carpenter Joiner.

One way to check for draughts, on a windy day outside, sprinkle some talcum powder down over the gap.

The Continental Op

OP, I very much doubt that is drying out or at least not drying out that caused those gaps. If you check around you'll probably find that gap is the same (give or take) on all the floors. The reason maybe and I have nothing to support this is that they were laid that way when lino was the main floor covering. That gap allowed lino to be fitted and the edges covered up.

I've lived in a good few old houses and they all had that gap. In some of them I removed old lino that was laid under the skirting boards.

While the floorboard have dried out and have gaps on either side of them the skirting board only has a gap between it and the floorboards. Thats another reason I'm suggesting the skirting was installed like that with a gap. However I can see the argument for the joists shrinking being the reason.

Captain Kidd

Thanks Everyone, lots to consider here, I’m relieved that it is not the result of damaged wood or something structural. There certainly is a as draft, I put plastic sheeting down while painting and quite often it lifted like a ghost! I like the idea of insulation under the floors. I’m assuming this entails pulling up all the floorboards? Sounds like an expensive job.

Captain Kidd

Lino under the skirting! Next time I am in the house I’ll check to see how continual the gap is. I’ve a feeling it was just in some sections of a room but will check again this evening when I am over. Thanks again

The Continental Op

LOL, one cottage we lived in the UK the carpet lifted whenever there was a strong wind in the South.

Really depends how you want to live OP. In the case of the cottage above we put down the thickest underlay then fitted carpet and then rugs on top of that and it suited us. Some people want to try and make a modern house out of an old one, if you have the money go for it otherwise work out ways of living with it.

C. Eastwood

Some softwood skirting boards are fitted at approx 18% Moisture Content (MC), with the Relative Humidity of most domestic houses, the timber will be air dried to the Equilibrium MC of approx 12%.

This reduction in MC will cause shrinkage of approx 3 mm in a 150 mm high Skirting board.

Captain Kidd

Thanks, it’s the floorboards I like though! I have some nice rugs but something underneath may be necessary, have yet to spend a winter in it.

C. Eastwood

https://www.boards.ie/discussion/comment/119460191#Comment_119460191

If there are draughts coming up between the t&g flooring and bottom of the skirting, there will also be draughts coming up between all of the shrunk t&g flooring boards.

Solution-

Remove skirting boards

Fill gaps between walls and t&g boards with expanding foam

Fit 1200 gauge Polythene sheet or airtight membrane over floor, bring the membrane up 100 mm on 4 walls

Bond the vertical up-stand of the membrane to the walls with mastic.

Fit underlay and new flooring.

Fit new skirting boards.

Second Solution:-

Fill gap between skirting board and t&g with silicone mastic

Fill all gaps between all t&g flooring boards.

Captain Kidd

Thanks really appreciate that. Would love to keep the floorboards so will look into filling gaps. Is there such a thing as lifting the boards and laying something underneath and then replacing the boards?

Thanks again

C. Eastwood

It is possible, but many of the boards will get damaged.

You will need advice from an Professional who is expert in Wet Rot and Dry Rot if you are fitting anything under the t&g flooring boards, if it is a suspended timber ground floor with Through Ventilation of the underfloor void.

Presently you have huge heat loss by Convection (Draughts), sealing the floor as I specified to stop draughts will reduce this heat loss.

Taking up the t&g flooring boards and fitting insulation under will give you a reduction in heat loss by Conduction. This will be expensive and will damage the flooring boards.

Reducing your heat loss by Convection is cheap and easy to do, and will give you a big reduction in heat loss.

Captain Kidd

Thanks that’s great, much appreciated. If you have any pictures of this I’d love to see. Is it generally not visible? Also would this be work a carpenter would have plenty of experience with or is a specialty. Thanks again, really appreciate it 👍🏼