Talk to me about external solid wall insulation.

We live in a victorian terrace with a passage along one side of the house. The house was extended about 3 years before we bought it and we’ve been thinking about a few different energy saving works: adding external wall insulation along the passage wall and the upstairs rooms at the back of the house, and underfloor insulation.

Conveniently, we’ve just had an email about a Green Deal and I’ve just spoken to the company about it. Unfortunately the woman wasn’t very knowledgeable at all and didn’t fill me with confidence. Effectively I’ve got to pay £50 up front to book a Green Deal assessment. I’d get a report and an EPC. Then I can book another survey, free, but with their contracted company, for any work that needed doing, get a quote and then proceed. Apparently there’s about £6600 available per property. So I asked what if the work was less and didn’t cost £6k? “It’s always is more” was her reply.

So, I asked a few other questions, who’se the contractor, are they local, can we see any of their current work, is it guaranteed etx… and she was struggling to answer anything. She offered me to speak to her supervisor, but he couldn’t come to the phone and will hopefully call me back.

Anyone here used or doing a Green Deal for this type of thing? What are your experiences?

Lastly, what should we have in mind when considering external wall insulation? Damp? Closures round windows, window sills, the eaves and guttering?
Thanks!

AVOID! Just contact some builders and ask them to trot along and explain what they would do to make your house warmer. A good builder will be very well clued up about insulation to the latest standards and new materials are extremely cost-effective.

I would certainly not add insulation to the outside of a house. We have just had a builder (cycling buddy so cash payment) dry-line a very cold bedroom in an extension and the result has been astonishing; okay we lost a couple of inches in size but from being permanently freezing the room is now the warmest and quietest in the house and a really nice place to be.

We had battens fixed on the walls with Kingspan in between then a covering of thin plasterboard backed with polystyrene. We took down the sloping ceiling and put in thick Kingspan before re-boarding.

We’ve thought about internal insulation but the two bedrooms upstairs are quite small to start with. Was it literally just 2 inches off each wall?

That is a sales company – go direct to Green Deal, and you get to choose your contractor (from the list of those listed). Go on recommendation, and do go and see their work.

External wall insulation is fabulous, works well and more than proven. It does need a good installer, who knows their beans and can get workmen to really take care over detailing.

Dry lining the way to go as globalti says. Quick easy and effective. 2 inch per wall would be max imo

Fairly blanket statement there globalti , why would you “certainly” not add insulation to the outside ?

We drylined a mates house over the summer there , its made a hella difference but im not in a rush to do mine…..council are looking to do external on the houses up the road….i may get a quote from the guys once the first couple houses are done, a friends flat in a difference council area not only looks much better ( insulated then rerendered) but it is loads warmer apparently halfed their heating bill

With the stove for heating id like to retain the thermal mass

Two of our neighbours have insulted on the outside with polystyrene with satisfactory results. One was about seven years ago. The stories of mould and damp I’ve seen have mainly been German. The higher cost (our neighbours paid 30 000e) and thermal bridges around the windows, doors, roof and floors put me off so I insulated on the inside. No thermal bridges around windows, or around the roof or floor insulation, but obvious ones where partition walls join the external walls.

I would certainly not add insulation to the outside of a house

Why?
Most of Europe do this, as standard, on old and new houses. In fact, our suppliers in Germany and Switzerland would rather do external than internal because of interstitial condensation.

So you add external insulation trapping in any moisture on the brickwork beteween the insulation and inside.

also the window cills externally need to be extended, and the outside walls re clad with a plaster skim.

Dry lining is less disruptive, one external wall,window cill easily made wider, plugs hust extended outwards on samll spurs, good reason to add new plugs and wiring etc.

I have a flat in a 1950s block which was done two years ago. They added 110mm of solid insulation and rendered afterwards. A fair bit of effort was needed on the detailing. All the boiler flues needed replacing with longer ones, and replacing and boxing in of external pipework. New wiring for aerials and all the other bits and bobs on the outside. It’s a first floor (of three)flat with a gable end, enclosed common stairwell. Looks really good, as the quality of the work is good. Inside, if there wasn’t already a gas boiler, I don’t think I’d bother, it’s transformed the place.

So you add external insulation trapping in any moisture on the brickwork beteween the insulation and inside.

Try googling Pavatex.

Yes outside detailing is an issue, but good installer/suitable building it is not a big issue..

Loads of houses having it done in Cambridge at the moment, looks terrible till they render / stick fake brick cover over it. Must take a photo of this one finished, it looks very good, hard to tell it has been altered.

External Insulation by brf[/url], on Flickr

I have no knowledge in this particular area but if I owned a nice stone built Victorian house I wouldn’t want to loose my box skirtings, dados, picture rails and cornices by lining out the interior; having no eves overhang and ogee rhones I would be concerned where the water off the roof was ending up with exterior cladding fitted plus I would be sad to see my nice stonework disappear.

I’d rather lose a few period features than pay some despot leader for his gas/oil. Quite apart from having a lesser role in submerging someone’s island home.

I have no knowledge in this particular area but if I owned a nice stone built Victorian house I wouldn’t want to loose my box skirtings, dados, picture rails and cornices by lining out the interior; having no eves overhang and ogee rhones I would be concerned where the water off the roof was ending up with exterior cladding fitted plus I would be sad to see my nice stonework disappear.

I agree. Some houses will never be really well insulated, for practical and aesthetic reasons.
My 1970’s Barrat house, would be hard to make worse from aesthetic and practical detailing on the weatherproofing… 😀
What can be done should – but let us not assume one size fits all.

We have a 1920s semi, no cavity wall, dry lined inside. the original render was blown and there is barely any cement in the mortar meaning the only way forward was to have it re rendered. I took the opportunity to insulate externally. Green deal estimate was £4-5k (no official assessment done, just the guys gut feel). Without the green deal grant (which wasnt available at the time) he estimated £8-9k.
I found a firm that stuck 100mm on and rendered £3.2k all in, the detailing was excellent – I couldn`t be happier with the result.
It`s been done two months and so far my gas bill is 20% down on last year – I appreciate the weather conditions may not be exactly the same.
Only downside I can see so far is more more condensation on the bedroom windows that are used. What was previously condensation 1″ from the bottom of the frame is now 5-6″. Just bough one of these – http://shop.dryhomes.net/collections/positive-input-ventilation

Shame about the first reply. 🙄

Had ours done 18 months ago.
40% reduction in gas consumption so far.
It’s a mid 60’s Wimpey “no-fines” construction.
House was transformed. Condensation mould problem on a couple of internal walls dried up straight away.

With regard to funding, Green Deal is a very expensive way of funding it, better to fund it yourself. Your looking at about £5-£6k for a typical 3 bed semi, but depends on the finish. It’s finished with a coloured silicon render, but you can have brick slips. They are pricey though. The finished job depends on the small details. Bevelling window apertures etc, it can make a big difference.

My advice would be, contact your local housing associations, & ask who they used. Then approach them directly.

When we had ours done there was a big pot of ECO funding, but it went quickly. The Energy Saving Co-Op were heavily involved, who were basically a middleman. The idea was that they would buy-in the materials, contractors etc, & work with smaller initiatives to role it out. Some of the smaller initiatives were often just local energy groups etc.

Don’t be put off by scaremongering. Most of Europe & Ireland have been installing these systems for years. It’s well proven & the results are excellent. Happy to answer any questions. If your anywhere near the Midlands your welcome to come take a look.

Just contact some builders and ask them to trot along and explain what they would do to make your house warmer. A good builder will be very well clued up about insulation to the latest standards and new materials are extremely cost-effective.

I would certainly not add insulation to the outside of a house.

Well you’re a fine one for advice. Most builders don’t know the first thing about building science, hence why you’ve probably given such duff advice about external insulation.

As matt said, it’s been far more common across Europe for far longer. The UK is getting to grips with it and it’s becoming far more common and that is a very good thing. You can get far more insulation outside than you can inside, so that’s in your favour. You also have an insulated external layer with a solid thermal mass inside, and that is the optimal place to have any thermal mass in a building.

OP – look round for specialist external insulation contractors in the area and seek recommendations. It’s a very good way of improving the performance of your house.

Takisowa, where in the midlands are you out of curiosity? I’m over Dudley way and looking to get the house done, along with a load of other simultaneous repairs (windows, roof etc) that’ll bollix up the finish if I do them subsequent. Anyone have an opinion on getting one company in to work it all as a project vs a different bunch for each job (I’m hoping the former’s sensibly viable, as the latter gets me flapping and procrastinating).

From having a quick squiz at green deals a while ago, I thought they were now either defunct or heavily means tested? I don’t really expect to qualify for anything , being employed and childless, but just in case…

I can accept that exterior cladding would be fine if your house looks awful but many people are quite happy with the exterior appearance of their houses and wouldn’t want some fake brick or stone cladding applied over the insulation. I’ve seen a new house built around the outside of an old house and it was done well with nice stone so looks like a nice modern house. But supposing you lived in a house with decent Victorian detailing or traditional northern stone?

Interior is easier to do and allows you to redecorate the house with a clean slate as well as make small changes to plumbing, sockets etc. If you have nice interior detailing, it would surely be possible to line the exterior walls up to the coving?

Having seen how easy it was with our extension and how unbelievably effective, I wouldn’t hesitate to dry-line the outside walls of an entire house before moving in, if I ever bought an old one with poor insulation. Dry-lining, re-boarding ceilings and skimming are so relatively cheap and quick nowadays and as I’ve mentioned, you’ll save on redecorating costs if you are starting afresh and not having to deal with somebody else’s hideous wallpaper or artex or blown plaster.

I would approach this with caution. I have been offered external wall insulation under green deal. Six months ago my council blanket visited all the houses in my neighbourhood heavily pushing external wall insulation.
. However the approved contractors for my council are completely useless. After signing the various contracts / grant forms and arranging a fitting date, they realized that they can,t actually fit external wall insulation to a house with bay windows – this is after 2 surveys and 3 visits when this problem was not identified. F***wits.

I have no knowledge in this particular area but if I owned a nice stone built Victorian house I wouldn’t want to loose my box skirtings, dados, picture rails and cornices by lining out the interior;

Just refit them over the insulation. When I next decorate the front rooms in the house I’m going to take off all the plaster and replace with 50mm Celotex with PB face and refit all the features (skirting, dado, picture rails etc).

Best solution yet from footflaps, above.

I reckon the invention of Kingspan or Celotex or whatever you call it has revolutionised home insulation because a thin sheet of this material has an insulation value far greater than a thick sheet of polystyrene foam, for example.

footflaps – living in an old Victorian house I’m wary that removing such original fittings would be easily removed in tact but I’ve never tried.

Have spent past 2 months working on houses that have external insulation with brick effect finish on them. All very warm, no sign of condensation and didn’t realise it had been done till someone told me. I would go for internal myself purely because I could get it done way cheaper. Have heard very few good reports about green deal/insulation style offers from people in the building game. Avoid all agent type people like the plague.

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a thin sheet of this material has an insulation value far greater than a thick sheet of polystyrene foam, for example

Do you like misleading people intentionally? Not a representative comparison at all.

Further info:
External
Internal

External insulation usually out-performs internal, but costs more. If you have a house that needs re-rendering or similar, then it might be worth you looking into it. If not, and you can cope with the disruption and loss of internal space, internal MIGHT work for you.

Nowhere to put your hanging baskets

Interestingly I haven’t heard back from the green deal manger guy, and I doubt I will from the comments above.

I’ll call the council and get a list of their approved fitters and try to speak to a few of them for summer quotes.

Spud-face…in Lichfield mate.
If your ever heading to the Chase any time, give us a shout.

I’d be tempted to get the windows done first.
Can be done after but risks spoiling the insulation.

Not all properties can have EWI. Listed buildings, conservation areas etc, have to have internal insulation.

It’s swings & roundabouts as to which method is best.
For older properties, especially solid wall ones, it works well because the existing wall is insulated, & hence any moisture is no longer meeting a cold surface.

footflaps – living in an old Victorian house I’m wary that removing such original fittings would be easily removed in tact but I’ve never tried.

I’ve taken all my 1890s skirtings off, sanded them on a bench and then refitted. NB You can buy matching stuff from builders merchants and just stain to look old (looks identical from a few feet away) – I’ve fitted them to the extension to match the original bits of the house.

NB You can buy matching stuff from builders merchants

Not always. Try walking into Howdens and asking for skirting in 14″, or swan neck coving in 9×12″, dado in 4″ double moulded, picture rail in 3 x 1 1/2″. It just isn’t there, and recreating it when it’s damaged isn’t trivial.

My builder’s merchants will just make it to order. They have all the moulding cutters and can pretty much make anything you want if there’s a cutter for it.

External depends on the look of your house.

This looks bluddy awful, it ruins the symmetry of the terrace and I would have big concerns about water ingress from above:

This on the other hand doesn’t look too bad, possibly even better than the original:

Funnily enough takisawa, I was planning to make my debut at the chase this Saturday till a family thing came up. Hoping to pop up next Friday afternoon if I can find the motivation – two trains each way saps my enthusiasm. Mine’s a Victorian end terrace, so pisses out heat like nobody’s business – with all this talk on here I’m tempted to do the inside as well whenever decorating time comes around. The render’s borked on mine anyhow, and doesn’t seem worth the faff of trying to constantly patch it. It’s just,a question of finding a reliable company. As useful as these “dodgy builder” telly shows and trusty trader websites possibly are, they play on everyone’s terror of having their castle pillaged – makes me paranoid from the get-go