Fill / Seal gap in floorboards

[Thomas71]

Just bought a house.... and posting my first question to this forum!

I will sand the floorboards (traditional/basic pine) of my living room/dining room.

As is always the case, there are 2-5mm gaps between the floorboards. I wonder if - for insulation reason - it is possible to fill these gaps. And if so, what should i use?

I thought that I should first sand down the floor boards (I will hire a floor sander) once, possible use the sawdust + mix it with a sealant (of which sort?), insert it, let it dry and then do the last sanding.

Is that sensible - what experience is out there??

M thanks

 

[WoodYouLike]

Is it an 'old' house: i.e. floorboards on joist with a ventilation area underneath it and are the boards T&G?

Filling the gaps will only be a temporary 'solution', movement of the floor will loosen any filler and drop down into the ventilation area.
It will not stop the draft, nor the dust and spiders coming into your room from the ventilation area I'm afraid.

Original floorboards in older houses you must see as 'modern' concrete floors in newer houses: underfloor on which you install other floorcovering to create a comfortable 'climate'.

 

[Zampa]

Cuprinol make a very good range of flexible sealants ..similar to caulk.

 

[Thomas71]

Thanks for both answers.

The house was built around 1910-1920 and the floor boards are fixed straight onto the joists / above the ventilation area.

Sorry dont know what "T&G" means.

Maybe getting some nice - new - floorboards on top of the old ones is the best (and most expensive) way forward.

 

[WoodYouLike]

Tongue and Groove

 

[Thomas71]

Another new abbreviation learnt today!

No it is not T&G; just bog standard pine boards nailed to the joists.

Floorboards are in very good condition (despite age) so I was hoping that it would be possible to achieve some form of draft insulation - even if it wont last forever - that would allow me to continue to use the floorboards (as are) but reduce the draft + increase insulation.

thanks

T

 

[WoodYouLike]

An idea might be to lift the existing floorboards, install 18 - 20mm plywood sheets on the joists and re-install the floorboards.
(But beware of the needed ventilation).