100 year old wood floors, under floor insulation

rob1976

My floor boards are 100 years old, tongue in groove and are in good condition.

There is a 2-3 ft crawl space under the floor.

However, the draughts are terrible, even with rugs.

I don't want to lift the boards to insulate as the would be damaged.

Has anyone experience of spray foam in this scenario?

Sleeper12

I'm pretty sure that you need a space between floor and sub floor. This should be vented for to allow the timber floor breath. I'm happy for someone with more knowledge to correct me

my3cents

I agree its probably not a good idea to seal the floor from below. The reason its lasted the 100 years is due to the "ventilation". You can't block off the exterior vents either but you might stop the wind blowing directly into the vents with a panel that only lets air in from below placed over them.

Sleepy

There are lots of solutions for sealing up the gaps between the floor boards, from wedges of matching wood which can be hammered into the gaps through to liquid sealants and simple plastic v shapes which slide into the gaps and are pushed down to be invisible. An old fashioned solution would be using strips of newspaper...