Foam insulation underfloor?

mdori003

I know foam insulation in loft spaces is generally frowned upon and can effect mortgagability of properties - does this apply for under suspended floors? I imagine some concerns around trapping moisture around joists may be the same but at least there are airbricks etc.

You know you are cold when you are googling robots that spray foam

Windofchange

In spring next year I’m going to be taking up all the downstairs floorboards and putting in insulation - probably PIR boards. It’s an easy enough job but will be time consuming for sure. I have to replace the water mains and move a couple of radiators so it’ll be worth the time to just do it all at once. You can get companies out to spray underneath with minimal disruption as you are getting at above, but I can only imagine that will be £££’s. Don’t see it being an issue with rotting the joists personally as like you say you have air bricks to keep things moving down there - just don’t block them up!

If you want some good instructions on various things search for gosforth handyman on YouTube. Take a look at his underfloor insulation video as a starter. 

mdori003

Thanks @Windofchange. That would be my thoughts too. I think the spraying robots are probably the only option as we had parquet flooring and screeding below that so it would be a nightmare to try and put something in DIY. I'm trying to draft proof the floor as much as I before getting a quote as I assume it will be obscene amounts of money as you say but who knows

Windofchange

mdori003 said:

Thanks @Windofchange. That would be my thoughts too. I think the spraying robots are probably the only option as we had parquet flooring and screeding below that so it would be a nightmare to try and put something in DIY. I'm trying to draft proof the floor as much as I before getting a quote as I assume it will be obscene amounts of money as you say but who knows

If you have screeding down you are possibly pretty well insulated anyway? Not sure what extra benefit you’ll get on insulation. Some perhaps but if wall to wall then any drafts etc will be pretty effectively blocked. Ours is suspended on a 2 foot cavity so plenty of potential to improve. 

mdori003

Floors are freezing and have noticed air around skirting boards. Only realised it when I started running dehumidifier whilst drying clothes and realised all the moisture was leaving the room anyway! 
Probably best shoring up all the little drafts properly first though anyway, darn sight cheaper.