Insulating from outside

[joddle]

Hi - I am hoping someone here will know what to do.

I live in Spain and part of my house is on the second floor but the space underneath some of the rooms is open to the elements and there is no possibility of enclosing that space. Normally there is no problem as the climate here is very mild but in recent months the weather has been very much colder than normal and we have noticed that the floor gets very cold indeed making one of the rooms very cold indeed - so much so that the inverter heating system really has a problem warming the space adequately.

The floor of the room concerned has ceramic tiles laid onto cement screed bonded to a concrete beam and block fill floor. Underneath that is fresh air.

Underneath there is plenty of room to add material before it would show or become a problem and so I have decided to insulate from the outside BUT am wondering what material to use.

A local builder suggested glueing insulating foam sheets to the underfloor but what type would be best? - I would like to try and avoid more heavy construction and don't really want to form a false ceiling and then fill the space between it and the floor above with insulation. The space involved is approx 20sqM

 

[noseall]

deja vu?

 

[joddle]

deja vu?

What a memory - and many thanks for that - and no I am not ignoring that advice but have moved on from the draughts etc which are now sorted leaving the cold floor problem which over the past four weeks has become even more of an issue due to dramatic temperature drops - what I really want to know is if there are alternatives to those products and more specifically how to glue or fix the insulation up there - ie is glue a viable fixing? and if so what type.? My local builder suggests using spray foam as an adhesive but is also concerned that the lighter weight insulation panels my not last long in an exposed position or get pecked to pieces by the swallows - not sure if that is a real possibility but perhaps one of you knows better - and I always like to listen to any advice before I commit myself to a course of action

 

[Deluks]

Inso boards left on site and exposed in the UK don't get pecked by birds (AFAIK) so why should it happen there?? Maybe your builder has been watching The Birds (and not the normal sort of birds that builders are associated with watching!)

Spray foam could be the answer here. Was in Madrid couple of weeks back, and where older properties/apartment blocks are demolished next to an existing property, sprayfoam is use to seal the existing wall (no sign of pecks!) So it is definitely available in Spain. Kingspan I know is also available in Spain.

Maybe your builder was putting you off of a solution that requires you to contract specialist installers and thus diddling him out of getting the job?

Only issue with sprayfoam is that the sun breaks it down over time, but shouldn't be a problem in your sheltered location.

 

[joddle]

Many thanks for the above post - it seems spray foam may be a viable adhesive and certainly it won't get any exposure to the direct sunlight. There seems to be several type of foam available from the dark yellow stuff seen on the outside of buildings as stated above or a white foam which seems to be very hard when cured. Does anyone have experience of the different types? or are there alternatives adhesives to consider?

On the insulating panels - I have previously been advised against polystyrene although it seems to come in very thick slabs and have been looking at Celotex which is readily available and I would like to know more about Kingspan which I have not come across so far but understand can be supplied here - what are the relative merits/disadvantages of these two products? any help most welcome.

 

[mointainwalker]

Polystyrene is brittle and easy to break when carelessly handled but in most countries only 30% ish of price of PU/PIR. I can buy any thickness from 20 mm to 100 mm at my local builders merchant/

PU/PIR is hard enough to stand on (irrelevant here) Insulates up to 60% better for same depth as polystyrene but costs 300% more as said.

Since you have Unlimited depth, I would suggest using as much poly as you feel is needed to keep yourself warm. How much is being discussed by you and your builder ?

I know birds are very prone to tearing away at any exposed fibre-wool but have not seen any attacks to poly.

I have had some exposed for several years with no bird damage.