Insulation on old house
Discussion
Evening all,
Got a question for the masses out there after emailing Kingspan and being very disappointed with their lack of any form of technical help regarding the build up of insulation on my ~200year old Welsh longhouse farmhouse in Shropahire. (Non-listed)
I'm after info on whether to dot and dab insulated plasterboard or to membrane-batten-insulation (taped) - batten - plasterboard.
I'm leaning towards the s cons as I can control the vapour barrier more and stagger the joints - maybe use 50mm insulation and 37.5mm insulated plasterboard.
I'm not into wool/eco as I want the best performing product to compliment GSHP throughout with a couple of open fires and a logburner for ambient/feature heat.
My Mrs has an Instagram account detailing her side of the renovation (won't post it on here in case it's seen as publicity/advertising etc)
More than happy to share plans/ideas, but don't want to commit to a full-on build diary.
I may start a sperate thread with final plan layouts to check there isn't something I have missed in the design/rejig.
If anyone has been through a similar process, I'd be grateful if any pointers.
In a nutshell we have to date:
Re-roofed half in random diminishing Welsh slate (looks stunning)
Stripped off cement mortar on all internal walls
Dug up the floors, insulated, screeds with UFH pipework in
Re-laid first floor joists and floor throughout.
This summer's jobs are pointing (both inside and out), relay the well pipework and collector tank
Commission the GSHP
Hopefully design a drainage system to carry rainwater from the yard.
Both the Mrs and I are office bods by day, so this is more of a hobby.
Cheers
Tom
Got a question for the masses out there after emailing Kingspan and being very disappointed with their lack of any form of technical help regarding the build up of insulation on my ~200year old Welsh longhouse farmhouse in Shropahire. (Non-listed)
I'm after info on whether to dot and dab insulated plasterboard or to membrane-batten-insulation (taped) - batten - plasterboard.
I'm leaning towards the s cons as I can control the vapour barrier more and stagger the joints - maybe use 50mm insulation and 37.5mm insulated plasterboard.
I'm not into wool/eco as I want the best performing product to compliment GSHP throughout with a couple of open fires and a logburner for ambient/feature heat.
My Mrs has an Instagram account detailing her side of the renovation (won't post it on here in case it's seen as publicity/advertising etc)
More than happy to share plans/ideas, but don't want to commit to a full-on build diary.
I may start a sperate thread with final plan layouts to check there isn't something I have missed in the design/rejig.
If anyone has been through a similar process, I'd be grateful if any pointers.
In a nutshell we have to date:
Re-roofed half in random diminishing Welsh slate (looks stunning)
Stripped off cement mortar on all internal walls
Dug up the floors, insulated, screeds with UFH pipework in
Re-laid first floor joists and floor throughout.
This summer's jobs are pointing (both inside and out), relay the well pipework and collector tank
Commission the GSHP
Hopefully design a drainage system to carry rainwater from the yard.
Both the Mrs and I are office bods by day, so this is more of a hobby.
Cheers
Tom
Talk to Ty Mawr - www.lime.org.uk - they'll give you loads of helpful info, and stock proper old-house-friendly building materials. Eco doesn't have to mean s
t.
t.I did both in my house.
I started with a load of seconds insulated plasterboard which we dabbed on - whilst there was no issue I wasn't happy sticking to foil
We then ran out so I fixed battens to the walls and fixed through the (50mm) insulation - this took longer but I felt happier with it - obviously you loose a little more off the room and technically the screws cause cold spots.
2 yrs on - no issue with either method
I started with a load of seconds insulated plasterboard which we dabbed on - whilst there was no issue I wasn't happy sticking to foil
We then ran out so I fixed battens to the walls and fixed through the (50mm) insulation - this took longer but I felt happier with it - obviously you loose a little more off the room and technically the screws cause cold spots.
2 yrs on - no issue with either method
Morning all, thanks for the recommendations. I spoke to Ty Mawr lime and another couple of lime companies, but no products I came across had anywhere near the properties I needed.
I am aiming for a U value, and being a farmhouse, the rooms are not the most generous of sizes so don't want to be losing any more interior space than I need to.
The reason I need better insulation properties is that I am going to be running a ground source heat pump, so I need the property well insulated.
The house does have a relatively high level of heat retention due to the 18" stone walls with rubble infill, but does take some heating - currently a Rayburn MF running smokeless pellets - but this only heats rads in three rooms.
I'm yet to come across a breathable solution that has the same (or very similar) insulation properties as a size-for size thickness of PIR board.
As for the lime plaster - I'm keen on this purely for the aesthetics - would use lime over plasterboard for its texture - but realise it it isn't allowed to do its job with a vapour barrier between it and the wall.
For those that are interested - the Instagram account the Mrs is using is called 'dreamhomebeingmade'
Thanks again
Tom
I am aiming for a U value, and being a farmhouse, the rooms are not the most generous of sizes so don't want to be losing any more interior space than I need to.
The reason I need better insulation properties is that I am going to be running a ground source heat pump, so I need the property well insulated.
The house does have a relatively high level of heat retention due to the 18" stone walls with rubble infill, but does take some heating - currently a Rayburn MF running smokeless pellets - but this only heats rads in three rooms.
I'm yet to come across a breathable solution that has the same (or very similar) insulation properties as a size-for size thickness of PIR board.
As for the lime plaster - I'm keen on this purely for the aesthetics - would use lime over plasterboard for its texture - but realise it it isn't allowed to do its job with a vapour barrier between it and the wall.
For those that are interested - the Instagram account the Mrs is using is called 'dreamhomebeingmade'
Thanks again
Tom
As has been said insulating old walls like these can create issues with damp etc.
I did some calculations for a friend with a similar house some time back, he was using 8k of oil / year (I think the gardener was nicking it, but that's another story).
He only used the house at weekends and it always seemed cold, when I did the heat loss calcs the wall u value wasn't too bad about 2.5w/m2/deg c from memory, the problem was that the thick walls had such high thermal mass that he put the heating on when he got home on Friday and the house didn't feel warm until Sunday when he left, because of the thermal mass (like a bid radiator) the house stayed warm until Tuesday.
He could have overcome this to some extent by either maintaining the house at a setback temperature, or switching the heating on on say Wednesday.
I'd suggest doing heat loss calcs to understand where the biggest improvements can be made, roof and windows (if not double glazed already) can have a huge effect on heat loss.
Is the GSHP sized for the house as it is now, or is it based on the insulation levels you are trying to achieve?
I did some calculations for a friend with a similar house some time back, he was using 8k of oil / year (I think the gardener was nicking it, but that's another story).
He only used the house at weekends and it always seemed cold, when I did the heat loss calcs the wall u value wasn't too bad about 2.5w/m2/deg c from memory, the problem was that the thick walls had such high thermal mass that he put the heating on when he got home on Friday and the house didn't feel warm until Sunday when he left, because of the thermal mass (like a bid radiator) the house stayed warm until Tuesday.
He could have overcome this to some extent by either maintaining the house at a setback temperature, or switching the heating on on say Wednesday.
I'd suggest doing heat loss calcs to understand where the biggest improvements can be made, roof and windows (if not double glazed already) can have a huge effect on heat loss.
Is the GSHP sized for the house as it is now, or is it based on the insulation levels you are trying to achieve?
Gareth H,
The calcs have been specced with the insulation included - I'm definitely not going to compromise on this as the system has cost an absolute fortune - I can see exactly what you mean about your friend's place taking an age to heat up - my place is the same, takes two days to feel 'warm' (that's an overstatement) but once it's to temp, remains fairly comfortable for a long time. Both the Mrs and I work all day in the week, but that's one of the things I loved about the ground source heating in the last place - it was on 27/7.
For info, mains gas isn't an option as we are so rural, oil isn't happening due to near impossible access - so we are left with coal or electric.
My plan is to insulate the uglier looking walls on the inside, and keep the better looking stone exposed (with new lime pointing). If that's too cold, will add insulation as required.
I will look into a decent heat demand survey though, but we are fixed with a 6-12kW invertor driven heat pump to heat a total of 360m^2.
All done to current building regs levels of U value, including a glass gable and conversion of existing attached outbuilding.
Thanks again
Tom
The calcs have been specced with the insulation included - I'm definitely not going to compromise on this as the system has cost an absolute fortune - I can see exactly what you mean about your friend's place taking an age to heat up - my place is the same, takes two days to feel 'warm' (that's an overstatement) but once it's to temp, remains fairly comfortable for a long time. Both the Mrs and I work all day in the week, but that's one of the things I loved about the ground source heating in the last place - it was on 27/7.
For info, mains gas isn't an option as we are so rural, oil isn't happening due to near impossible access - so we are left with coal or electric.
My plan is to insulate the uglier looking walls on the inside, and keep the better looking stone exposed (with new lime pointing). If that's too cold, will add insulation as required.
I will look into a decent heat demand survey though, but we are fixed with a 6-12kW invertor driven heat pump to heat a total of 360m^2.
All done to current building regs levels of U value, including a glass gable and conversion of existing attached outbuilding.
Thanks again
Tom
LPG - forgot that... No can do either - access is via a 7foot wide very muddy rutted track - same reasons we discounted oil. Could do bottled gas at a push, but horrifically expensive I would imagine.
Anything bigger (or higher) than a defender is a no-go and we don't own the track to make matters exciting.
Anything bigger (or higher) than a defender is a no-go and we don't own the track to make matters exciting.
Pickup a trailer mounted bowser and collect/top up your oil yourself?
The savings will easily pay for the bowser and with a suitable electric pump setup it'll be fairly painless task once or twice a year. Appreciate you might not want the hassle though.
A friend installed an electric ground source heat pump to replace his existing oil boiler and it's proving so expensive to run that he's considering switching back. The claims made by the installing company were wildly optimistic apparently.
The savings will easily pay for the bowser and with a suitable electric pump setup it'll be fairly painless task once or twice a year. Appreciate you might not want the hassle though.
A friend installed an electric ground source heat pump to replace his existing oil boiler and it's proving so expensive to run that he's considering switching back. The claims made by the installing company were wildly optimistic apparently.
Edited by snowandrocks on Tuesday 27th March 21:57
Coupled with the constant runs of tonnes of sand/gravel/blocks/timber/slates I don't think I can handle more shuttle trips of supplies unless we have absolutely no option. Shifting 6T coal to power the rayburn was interesting last summer, but it did he job in the absence of a more efficient heating system.
The last house I renovated (a very local to me chapel conversion) the GSHP was absolutely fantastic. Cost about £50 per month to heat the whole house as well as constant hot water - and had no supplementary heating (fireplaces/logburners) either - so it's a technology I'm comfortable and familiar with.
My folks have oil - as well as being expensive to buy, it's also awful if something goes wrong which I had experience with growing up.
The last house I renovated (a very local to me chapel conversion) the GSHP was absolutely fantastic. Cost about £50 per month to heat the whole house as well as constant hot water - and had no supplementary heating (fireplaces/logburners) either - so it's a technology I'm comfortable and familiar with.
My folks have oil - as well as being expensive to buy, it's also awful if something goes wrong which I had experience with growing up.
tom_loughlin said:
The last house I renovated (a very local to me chapel conversion) the GSHP was absolutely fantastic. Cost about £50 per month to heat the whole house as well as constant hot water - and had no supplementary heating (fireplaces/logburners) either - so it's a technology I'm comfortable and familiar with.
Have you seen this thread?https://www.pistonheads.com/gassing/topic.asp?h=0&...
I can only say that two neighbours with farmhouses have discontinued with their GSHP because they couldn't insulate/heat them sufficiently to keep warm. In both cases stupidly expensive to instal in the first place.
I wonder if the emphasis should be that the heating system must meet the requirements of the house insulated as best you can rather than the GSHP dictating what you must do?
It seems most specifiers work on wishful thinking squared, but good luck!
I could have had boreholes or trenches for the cost of the diesel but didn't feel confident.
I wonder if the emphasis should be that the heating system must meet the requirements of the house insulated as best you can rather than the GSHP dictating what you must do?
It seems most specifiers work on wishful thinking squared, but good luck!
I could have had boreholes or trenches for the cost of the diesel but didn't feel confident.
Good luck but as others have said oil is dead easy.
Can be bought in 25 litre drums up to 900 litre IBEC it's no more hassle than gas unless it leaks which can be insured against for very little on house insurance
The issue with internal insulation is that you aren't (effectively) heating that large thermal mass, interstitial condensation could be an issue
Can be bought in 25 litre drums up to 900 litre IBEC it's no more hassle than gas unless it leaks which can be insured against for very little on house insurance
The issue with internal insulation is that you aren't (effectively) heating that large thermal mass, interstitial condensation could be an issue
As I said initially, I will be going with the heating system I have chosen. I have lived with it before, know it and love it.
Properly specced in a properly specced house it works perfectly for my needs.
I have seen the threads on it - each to their own and I can only comment on what I have direct experience of.
We are somewhat limited to options - yes there are ways round oil deliveries - but when we already have the house to be doing and materials to be collecting - everything needs collecting, nothing so far has been able to be delivered, the thought of yet more runs to collect supplies isn't a positive.
Tom
Properly specced in a properly specced house it works perfectly for my needs.
I have seen the threads on it - each to their own and I can only comment on what I have direct experience of.
We are somewhat limited to options - yes there are ways round oil deliveries - but when we already have the house to be doing and materials to be collecting - everything needs collecting, nothing so far has been able to be delivered, the thought of yet more runs to collect supplies isn't a positive.
Tom
tom_loughlin said:
As I said initially, I will be going with the heating system I have chosen. I have lived with it before, know it and love it.
Properly specced in a properly specced house it works perfectly for my needs.
I have seen the threads on it - each to their own and I can only comment on what I have direct experience of.
I asked if you'd seen that thread so that you might consider giving the benefit of your experience to somebody who sounds like they could use it...Properly specced in a properly specced house it works perfectly for my needs.
I have seen the threads on it - each to their own and I can only comment on what I have direct experience of.
TooMany2cvs said:
tom_loughlin said:
As I said initially, I will be going with the heating system I have chosen. I have lived with it before, know it and love it.
Properly specced in a properly specced house it works perfectly for my needs.
I have seen the threads on it - each to their own and I can only comment on what I have direct experience of.
I asked if you'd seen that thread so that you might consider giving the benefit of your experience to somebody who sounds like they could use it...Properly specced in a properly specced house it works perfectly for my needs.
I have seen the threads on it - each to their own and I can only comment on what I have direct experience of.
I had to undertake a Daikin heat pump course to be given dealer status, several others on the course were boiler engineers, quite logical as the heat pump is an alternative to a boiler. These guys were never going to have the skill sets to design an effective system.
OP if you are struggling with effective insulation I would spec a larger heat pump or possibly look at backboilers in your wood burners (I think you said you were installing?) and use a thermal store which is fed from both the HP and back boilers to supplement the heating when ambient are low. It would also give you a fallback heating system should there be issues with the HP
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