Cost of Internal Insulation

cosycosy · 03-12-2019 11:02am #1

Anyone know roughtly the cost of drylining a 4 bed semi? Bought a 1970s house with ZERO insulation

loyatemu · 03-12-2019 11:21am

cosycosy wrote: »

Anyone know roughtly the cost of drylining a 4 bed semi? Bought a 1970s house with ZERO insulation

external not an option? By all accounts it is the better solution.

keithdub · 03-12-2019 3:17pm

It might work out cheaper to do the external, you will need a plumber, electrician and plasters to do the inside and move all your stuff out of the house

Calahonda52 · 03-12-2019 4:15pm

cosycosy wrote: »

Anyone know roughtly the cost of drylining a 4 bed semi? Bought a 1970s house with ZERO insulation

.
IWI 125/m2
.
EWI 150-190 /m2
.
both plus VAT

Dardania · 03-12-2019 4:17pm

Calahonda52 wrote: »

.
IWI 125/m2
.
EWI 150-190 /m2
.
both plus VAT

Does the IWI cost include for moving M&E & finishes?

Calahonda52 · 03-12-2019 5:56pm

Dardania wrote: »

Does the IWI cost include for moving M&E & finishes?

Good question, I just saw them in a tender, need to peep at the rest, if I can

Cerco · 03-12-2019 11:08pm

For the EWL option you need to look at cost of moving utilities if not included in quotes.

Jocasta · 04-12-2019 10:26pm

We bought a 1970s house with zero insulation this year too! So far we have just had one room dry lined as couldn't afford more right now. We got the two external walls of the corner bedroom (room is 2.5m x 4.2m) done with 50mm insulation plus walls and ceiling skimmed for €1,050 - of note our house the radiators are on the inner walls so radiator didn't need to be moved. It has made a major difference to that room, but also our bedroom beside it feels warmer.

The front wall of the house is cavity wall so we had that pumped about two months ago, and the attic done too - it was €1,400 to get both of those done and we noticed a difference right away too.

GreeBo · 05-12-2019 12:35pm

keithdub wrote: »

It might work out cheaper to do the external, you will need a plumber, electrician and plasters to do the inside and move all your stuff out of the house

You also need to consider that your skirting all has to move, your architraves, your carpet, any coving, window boards, any tiled areas, mirrors, etc, etc.

External is probably still more expensive, but its a better job and you dont lose any internal area like you do will internal.

(External obviously also has extrusions to worry about (window sills, meter boxes, reveals etc)

Shefwedfan · 08-12-2019 10:23pm

I have done internal wall insulation in tow houses now

First, it was 70's build and semi D....I have to replace the windows anyway and the wiring was old so I stripped it down to external walls and put it back together. including floor and attic etc

Second was a bugalow built in 80's....again reasons for why I done internal

Now I was talking to a guy and he said the thinking now is external is better as the heat goes into the walls, hits the insulation and then goes back into the house.....to be honest I am not sure which is better. It just suited me to do internal

If I won the lotto I would slap external on it now as well :-)

Payton · 08-12-2019 11:05pm

I got quotes for external insulation by 3 different reputable companies, I live in a mid terraced house so it's front and back only to be insulated and the quotes were between 15k-21k. The price was out of my reach, I'm early 50's at the moment so I would like to see some kind of payback. Maybe if I was younger and early 20's I would reap the rewards of it.
I insulated all the external walls on the inside myself with 100mm as I was renovating and it cost me roughly 2k between buying the boards a new window boards sockets being moved etc including plastering and i can say the house holds the heat very well.

Dardania · 08-12-2019 11:10pm

Payton wrote: »

I got quotes for external insulation by 3 different reputable companies, I live in a mid terraced house so it's front and back only to be insulated and the quotes were between 15k-21k. The price was out of my reach, I'm early 50's at the moment so I would like to see some kind of payback. Maybe if I was younger and early 20's I would reap the rewards of it.
I insulated all the external walls on the inside myself with 100mm as I was renovating and it cost me roughly 2k between buying the boards a new window boards sockets being moved etc including plastering and i can say the house holds the heat very well.

How much?!

Our mid terrace 2 bed house was I think 6k less whatever the grant at the time was around 2013...

GreeBo · 09-12-2019 2:55pm

Shefwedfan wrote: »

I have done internal wall insulation in tow houses now

First, it was 70's build and semi D....I have to replace the windows anyway and the wiring was old so I stripped it down to external walls and put it back together. including floor and attic etc

Second was a bugalow built in 80's....again reasons for why I done internal

Now I was talking to a guy and he said the thinking now is external is better as the heat goes into the walls, hits the insulation and then goes back into the house.....to be honest I am not sure which is better. It just suited me to do internal

If I won the lotto I would slap external on it now as well :-)

Not much point in doing external if you have internal done, if the internal is done properly, the heat wont get to the core of the house so it cant act as a heat sink (which is the point)

listermint · 09-12-2019 3:46pm

if you do go internal Make sure Airtight tape is used first, then boards can go up.
Absolutely no use doing it if draughts are still blowing down the boards and out the skirting or sockets

GreeBo · 10-12-2019 9:09am

Payton wrote: »

I got quotes for external insulation by 3 different reputable companies, I live in a mid terraced house so it's front and back only to be insulated and the quotes were between 15k-21k. The price was out of my reach, I'm early 50's at the moment so I would like to see some kind of payback. Maybe if I was younger and early 20's I would reap the rewards of it.
I insulated all the external walls on the inside myself with 100mm as I was renovating and it cost me roughly 2k between buying the boards a new window boards sockets being moved etc including plastering and i can say the house holds the heat very well.

While that is expensive, remember that the payback is in terms of comfort as well as savings.
(Not to mention the increased value of your home)

BryanF · 10-12-2019 9:26am

GreeBo wrote: »

Not much point in doing external if you have internal done, if the internal is done properly, the heat wont get to the core of the house so it cant act as a heat sink (which is the point)

Is it the point? What about all the junctions/thermal bridges that iwi ignores

GolfNut33 · 10-12-2019 9:28am

GreeBo wrote: »

While that is expensive, remember that the payback is in terms of comfort as well as savings.
(Not to mention the increased value of your home)

This.

People just don't think about personal comfort with these things and its always decided on by cash.

GreeBo · 10-12-2019 9:40am

BryanF wrote: »

Is it the point? What about all the junctions/thermal bridges that iwi ignores

Do you disagree that installing ewi to cover the gaps left by iwi would be a very inefficient thing to do?

Do you also disagree that the reasoning behind ewi is to allow the fabric of the house to store and release heat when its required (compared to iwi that attempts to preserve warm air)?

Payton · 10-12-2019 12:06pm

GolfNut33 wrote: »

This.

People just don't think about personal comfort with these things and its always decided on by cash.

Unfortunately it boils down to having the cash to get the job done and as I said in my post to reap the rewards of the external insulation, will I save the best part of the cost against my heating at 52 yrs of age? I did the maths and I would not break even by the time I retire. I'm not knocking it but approx 20k could be better sent on other projects around the home.
My home is warm and insulated (walls and attic) there are no draughts that I know of, it was 6 degs yesterday evening and I put the gas (new boiler) heating on for an hour and the house was warm this morning as it is most mornings.

BryanF · 10-12-2019 10:24pm

GreeBo wrote: »

Not much point in doing external if you have internal done, if the internal is done properly, the heat wont get to the core of the house so it cant act as a heat sink (which is the point)

But,

Is it the point? What about all the junctions/thermal bridges that iwi ignores?

GreeBo wrote: »

Do you disagree that installing ewi to cover the gaps left by iwi would be a very inefficient thing to do?

Do you also disagree that the reasoning behind ewi is to allow the fabric of the house to store and release heat when its required (compared to iwi that attempts to preserve warm air)?

Do you agree that leaving the gaps at iwi walls, floors and ceilings can lead to cold bridging, surface condensation, and as a percentage of the envelope is worth considering?
Do you agree that preserving warm air internally, may require ewi because the fabric with iwi is not continuously warped in insulation?

BryanF · 10-12-2019 10:52pm

Terraced house.
Iwi wall area: 6w x h4.8(2storey) x2 front/back = (57.6 iwi total area) then calc thermal bridges covered by ewi: 0.25vert wall (x4) 2party walls & 2front/back (=1) x 5.4h (=5.4)+ .2 x 3 (=.6) ground floor/first/eaves x 6w = (5.4 + 3.6) = (thermal bridges 10) v 57.6 iwi (discounted opes assuming they cancel out whether ewi or iwi )

So ewi covers 67.6
And iwi covers 57.6

Is it worth doing ewi? It’s worth considering what’s not insulated with iwi.

GreeBo · 12-12-2019 9:42am

BryanF wrote: »

But,

Is it the point? What about all the junctions/thermal bridges that iwi ignores?

Yes, the point of ewi it to use the fabric of the house as a heat sink...are you disagreeing with this?

Do you agree that leaving the gaps at iwi walls, floors and ceilings can lead to cold bridging, surface condensation, and as a percentage of the envelope is worth considering?
Do you agree that preserving warm air internally, may require ewi because the fabric with iwi is not continuously warped in insulation?

I am 100% in favour of ewi for all the reasons you list above, what I'm not in favour of is doing both.
Doing both is a waste of money, the iwi will impact the performance of the ewi and the ewi will "only" be covering the % of gaps that iwi left behind.

Its not like glueing and screwing a joint for belt and braces approach, everyone should just do ewi if they can afford it, or wait and save until they can.

listermint · 12-12-2019 11:16am

GreeBo wrote: »

Yes, the point of ewi it to use the fabric of the house as a heat sink...are you disagreeing with this?

I am 100% in favour of ewi for all the reasons you list above, what I'm not in favour of is doing both.
Doing both is a waste of money, the iwi will impact the performance of the ewi and the ewi will "only" be covering the % of gaps that iwi left behind.

Its not like glueing and screwing a joint for belt and braces approach, everyone should just do ewi if they can afford it, or wait and save until they can.

I think EWI has to be done with an eye to also doing air tightness chances internally. It can be easily defeated with open access to attic spaces. or bad doors and windows

BryanF · 13-12-2019 1:32am

GreeBo wrote: »

Yes, the point of ewi it to use the fabric of the house as a heat sink...are you disagreeing with this?.

Is that the point? And is that an argument for not using ewi to solve a problem of a cold house that’s had iwi installed?
It’s a lesser point IMO than,
1. Increased Thermal comfort (often overlooked)
2. & Reduced risk/relocation away from walls, of surface condensation

GreeBo · 13-12-2019 1:46pm

BryanF wrote: »

Is that the point? And is that an argument for not using ewi to solve a problem of a cold house that’s had iwi installed?
It’s a lesser point IMO than,
1. Increased Thermal comfort (often overlooked)
2. & Reduced risk/relocation away from walls, of surface condensation

Well it's how EWI works, obviously "the point" of any insulation is thermal comfort and reduced costs. How this is achieved and how efficiently it works is the difference between iwi and ewi.
iwi keeps the air in your house warm, ewi keeps the fabric in your house warm.
its the difference between underfloor heating and a fan heater....but you know all this so I dont really understand why you are arguing about it...unless its some misunderstanding about my point. (but I dont feel I can clarify it any further tbh!)

Again, the I'm making is that it will be very expensive to get both iwi and ewi on a house, so dont bother with iwi and save until you can afford ewi.

horse7 · 09-08-2021 10:14am

Just came across this thread while trying to search cost of internal insulation for a 160 square metres detached house 1974 build, what's EWI and IWI mean, also any idea of cost to supply and fit 22mm insulated plasterboards to all outside walls?

Alkers · 09-08-2021 4:41pm

EWI is external wall insulation

IWI is internal wall insulation

They both refer to the external walls of the property, the difference being whether the insulation is on the inside face or the outside face.

FileNotFound · 09-08-2021 4:47pm

Went internal in our house - the real cost was in the replaster and labour.

Honestly cannot locate my expense sheet from the build or I could have given the exact figure (3 years old but would have been ballpark).

One thing I will mention and maybe someone here will have experience is have you considered using TE board and Tape & fill? Yanks seem to swear by it but not so common here, assume it would save a small fortune v skimming the place...

finnyob · 11-08-2021 12:00pm

https://www.boards.ie/discussion/comment/117726892#Comment_117726892

We're in the middle of doing this job (and a lot more besides) ourselves with internal insulation to our 70s semi-D in D6w. Builder has down €3600 for supply, fit and skim 63mm insulated plasterboard slabs to all exterior walls. As we've a suspended timber floor, we also are getting that insulated and an airtight membrane over that in order to cut heat loss through the floor for another €5700. If your house is similar with a suspended floor, you're probably stuck with internal insulation unless you were going to fill in the subfloor void and bring it up to the existing floor level, but again that's a much higher cost. You'll definitely find there will be other costs creep in, our floor levels were off in several rooms downstairs, but at least the joists and floorboards were all in good nick.

ripvanradio · 14-08-2021 11:03pm

Discussion here is all focused on personal advantage.

The big picture is that we need to reduce CO2 consumption, no matter what age we are and no matter what ‘payback’.

My experience is that EWI may be more expensive but is less intrusive and very effective. I have spent approx €35k (net of grants) to move a 1970 build from BER F to BER B2. Steps included replacing glass in windows, replacing oil boiler with a condensing model with heating controls, installing 14 solar pv panels (generating 4000+ Units p.a.) and finally insulating everything externally.

It doesn’t matter to me (aged 68) whether I get a personal payback, but I get great satisfaction out of seeing my reduced energy consumption. By judicious use of Bonkers.ie , I have not had to pay for electricity since March 2021 and I am in credit with my electricity supplier to the tune of €117.

Just do it!

10-10-20 · 19-08-2021 2:10pm

Just on the cost conversation - Back in Oct 2020 I ordered 50mm insulated plasterboard (PIR) from a well-known supplier here in Dublin and paid EUR 38 per unit (in VAT).

Now today, those same boards from that same supplier are 68.54 EUR (inc VAT). That's an increase of 77%.

All I'll say is: Shop around.

Cost of Internal Insulation

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