Another Insulation Question!!!

tinney

Hi all. we recently bought a house in lutrellstown built by park developments around 96/97. The problem is that it is a very cold house. House goes cold very quickly once heat is off. Ive been thinking of getting pumped insulation done but im not sure if the house is suitable or not. ive looked at bolckwork by opening a vent and im confused it looks like block on flat then batten for the plasterboard with insulation between (rockwool). Could this be correct and if so would anyone have any ideas on how to make the house retain heat better. many thanks in advance

sinnerboy

The likely construction here is 215 hollow block dry lined internally with 50 x 50 timber battens with fibreglass between . The solid block you saw at the vent is probably only solid local to the vent - but it is possible that the wall is all solid block . Very poor U Value in either case .

Solid blockwork naturally cannot be filled with insulation . Hollow blockwork can be filled but the solid parts of the block render this very ineffective .

You best bet is to look at external wall insulation .

Your attic is likely to have 150mm max insulation . This should be topped up to at least 300mm total ( i.e. 150mm top up )

If the boiler is the original one ( hope not ) it is likely running at 60% efficiency at best i.e. you are throwing away 40c per euro of fuel spent.

I doubt you have time and temperature control of your heating system
I doubt your cylinder has a temp. stat . Bet the lagging jacket is just that i.e. not factory fitted insulation .

All the above items can be addressed with grant assistance

http://www.seai.ie/Grants/Home_Energy_Saving_Scheme/?utm_source=constructireland&utm_medium=banner&utm_content=Banner&utm_campaign=HES

If you have recessed lighting in any parts of the house they are a source of air leakage ( drafts ) . Replacing with surface mounted fittings would help a lot - ( no grant for this )

tinney

Thanks very much sinnerboy your post was most helpful. External wall insulation seems to be pretty expensive even with the sei grant it would still be out of our reach. i found a dublin based company that claim they can pump in foam type insulation between the block wall and plasterboard without damaging or causing it to bulge.have you heard of this technique.could it be effective. i could pm details to you if you wanted to see yourself.

sinnerboy

tinney wrote: »

i found a dublin based company that claim they can pump in foam type insulation between the block wall and plasterboard without damaging or causing it to bulge.

I have not heard of this before - it sounds probelmatic . The internal cavity would need to be clear to receive the foam - you have stated there is already rockwool ( I suspect fibregalss) - so there is no where to pump the foam into .

Some houses built around late mid - late 80's were built with un insulated
( i.e. empty ) dry lining cavities . I would fear for electrical points located within such dry lining if the cavity was pumped .

Build Rite

tinney wrote: »

Thanks very much sinnerboy your post was most helpful. External wall insulation seems to be pretty expensive even with the sei grant it would still be out of our reach. i found a dublin based company that claim they can pump in foam type insulation between the block wall and plasterboard without damaging or causing it to bulge.have you heard of this technique.could it be effective. i could pm details to you if you wanted to see yourself.

That is rubbish, possibly if the cavity was empty it would help.

if you want to improve the house and not spend much, i would look at how airtight is.
as you have got some insulation, remember most of Dublins (older) houses dont have any insulation.

in fact i often find old houses that are warmer than 1995/96 built houses even though they have less insulation. simply because they have been built properly. internal dryling is a nightmare, it has so many air tightness problems