costing extensions/renovations during buying process

Am looking at properties that would need to be renovated/extended. Any advice on how best to quantify the costs/efforts required prior to making offers would be greatly appreciated?

Renovation work depends massively on the age of the house you’re looking at, and it’s current condition, of course.

Extensions will be more expensive on older buildings because there will probably be some particular structural works required when making changes to the openings. Also usually more work involved in changes/renewal of electricity meter and wiring, water supply pipes, sewage pipes etc… Also likely that particular finishes, windows etc will be required to suit the building.

Moved to Sell, Buy, Rent forum.

It might be worth your while having a long talk with someone you’d trust to do the renovations for you. If you’re definitely going to buy such a house and definitely going to hire a particular builder to do it for you, then it would be no harm to have them view the properties with you. It would seem like a win-win situation to me - you can’t be spoofed by the EA, the builder will be with you from the start and you’ll have a degree of confidence going into the purchase.

At the very least, contact a company that specialises in this kind of work and see what assistance they can offer or would suggest. It may even be the case that there are specialised builders or other experts who offer a service of this kind.

I just got a quote for the following:

new house, 2200 sq ft - €130k (including VAT), works out at €59/sq ft.

As there is no specification with the drawings, I just priced for bog standard - Smooth plaster finish and standard slate finish externally, white pvc Munster Joinery windows, standard plumbing and electrical installation and red deal internal doors, skirting and architrave.

Price is just for builders finish.

Excludes:- All siteworks, site clearance, drainage and footpaths.
Painting, floor finishes, tiling, built-in fittings.

this may help, although I know a renovation is a different story. But it shows how much prices have come down.

What was the construction method? Cavity block and insulated board, cavity wall or timber frame (or something else)?

The cost of building work had been grossly inflated during boom time, and this artificial level has seemed to remain etched in the minds of prospective purchasers to date. So much so, that they are put off properties that might only need a few bob spent on them to put them right. I have always priced fairly, but yet I have missed out on contracts in the past because people have considered me too cheap, therefore I must be a cowboy. Truth is, the real cowboys were the ones that would triple the actual cost and get away with it because they had a fancy van and website. (My neighbours were quoted €27k to build a side garage in 2006, had it built in 2008 when things slowed for €8k, by the same builder)
Based on a house circa 1500 sq. ft., of any age, you could leave the four external walls standing and completely gut and re design the inside from €40k upwards depending on spec, including rewiring, re plumbing, new kitchen/ bathroom, insulated to todays standard. New windows will cost from €5k for uPVC to €10k for nordic pine. A new roof would be between €10-12k, rear extension about €20k, wrap around extension about €30k. These are all ball park obviously, but should give you some indication.
However, because people expect to pay more, use this to your advantage when making an offer. €100k is a figure thats bandied about a lot for total refurb, and seems to be accepted as reasonable. The cost of extensions doesn’t usually come into play at the negotiation stage, unless there’s a DIY extension in existence that has to be knocked. Consider also, that a seemingly perfectly habitable house with poor insulation, dated kitchen and flooring/ decor that’s not to your taste will cost almost as much to re do as a house with mouldy ceilings and the plaster falling off the walls. I’ve personally bid on 2 properties in the past having never seen the inside of either.
Happy hunting,


Paddy - that is so timely for me I just have to say a big thanks :smiley: 8DD (in lieu of a blowing kisses smilie)

I’ve had an offer accepted on a small 1950s bungalow and I’m waiting for the surveyor to come back with his report but I know it will include: wiring, windows, insulation etc. I also have ideas for remodelling and a small extension but friends have been so scary in their top of head estimates that I’m nearly getting cold feet. What you just said reflects my own view and that of one friend who got a massive job done for 80K recently. I suppose the other pals who paid 150-300K for their own extensions would find it too challenging to accept the lower costs.

Cavity block and insulated board.

Dont know how it works in Ireland but in UK the rule of thumb is £1k/M² for single storey and £1.5k/M² for 2 storey.
This is for a DPC, build and roof.
No plastering, flooring or wiring is included.

EDIT - this for an extension I had priced up. I’m not sure about new build prices.

Well, yes, but that doesn’t tell ‘Harold Cross’ much, does it? How long is a piece of string?

Most people might think you’re a bit optimistic expecting to make anything decent out of a 1500 sq ft gutted Victorian house with €40k. Renovation work on these buildings usually attempts to maintain the Period features and work around them, not gut them. It is far cheaper to renovate a 1950’s block built house than a lime mortar/red brick Victorian house.

A 1500 sq ft Period house (typical of the better roads in Harold’s Cross)? I wouldn’t expect to do a major renovation job including traditional teak sash windows, re-slating, lead valleys, insulation, a decent kitchen extension and bathroom for less than 90k. And another 10k for decorating. I doubt if this could be turned into this for less than 120k.

+1 needle. That sounds about right.

Thank you Coles2, you’ve just proved my point entirely. Its because of beliefs like this, the general populace has been fleeced for years. I take your point that period renovations are more labour intensive, but that’s for the most part counterbalanced by a saving on materials, unless the place happens to be a listed building that’s been hit by a bomb. The lime mortar you mention is a classic example of Tiger construction inflation. ’ Specialist’ plasterers used to charge upwards of €100 per m2 for lime rendering, whereas the sand/cement equivalent would be about €20 per m2. The only difference essentially between the two methods from an application point of view is the curing time necessary between coats. The labour element is more or less the same, and materials for lime render mix are actually cheaper. It meant that the ‘specialist’ could spend tuesday to friday on the high stool waiting for his lime to cure, and still come out with the same coin as the poor sand/cement guy who had to work the whole week.
I’ve actually refurbed a five bed on the Harolds cross rd. complete with roof repairs, new joisting, 2 fully tiled bathrooms, rewiring, plumbing, slabbing, plastering, carpentry, flooring and painting for €38k + VAT, and I did alright out of it myself. The proof of the pudding is in the eating. Had Harolds Cross told me how long their piece of string was, ie. drawing, spec, maybe I could have been a little more helpful, but at the end of the day, it’s a discussion forum, not a tender process.

Good man. Thanks for this very useful contribution.

The Society of Chartered Surveyors Ireland produce details on rebuilding costs: … -Guide.pdf

I always feel that renovation costs are considerably overestimated in this forum. I have done the same renovation thing a few times and spent a lot less than the numbers quoted here.

I saw a late 1800s house at the weekend where all the “plastering” consisted of studding all the walls, leaving loads of room for the obvious rodent infestation, judging by the number of rodent traps all over. It was so crap, cheap and nasty Celtic Tiger shite.

Drop a cheque around for 120K anytime and I’ll do the work and make a handsome profit.

And it’s right that you should make a profit, no? But I’d also expect you to do the job properly so that it would last longer than it takes to cash the cheque.

Really? How long did it take you? How did you insulate the interior of the external walls? What did you do to the ceilings and covings? What windows did you install? Did you keep the shutter boxes?

2000 sq ft 5 bedroom Period house renovated to a high standard for 38k?

€19/sq ft?

Couple of assumptions made there. Never said it was a period house, post war stone built, had been in flats, so no cornice/ shutter boxes, and already double glazed. Also more like 2500 sq. ft. Took two of us 4 weeks, with visits from a plumber and electrician for first and second fix as required, and a painter for a few days at the end. Used 80mm polyurethane backed plasterboard mushroom fixed to the window walls, brought in 1.2m down each gable wall to counter thermal bridging. (The house is mid terrace). All the old latted ceilings had to come down as the joists were rotten. Used fireline plasterboard at ground level, and foilbacked on the upper levels. All for just over €15 per sq. ft.! Impossible, right?

Materials, including flooring/tiles/paint- €9.5k
Kitchen- €7k
Electrical, excluding alarm- €4.5k
Plumbing, including new boiler/ rads/ sanitaryware-€6.2k
1 man x 4weeks- €3.2k
Painter- €500
Skips- €500
My poke- €The balance

When it’s broken down, it’s easier to see where the money is going. It also makes it hard to hide big bump ups, as anyone can phone a builders providers and check the price of things for themselves.

I don’t really agree with per square foot generalisations for renovation costs, as each job is totally unique.

Hope this makes things a little more believeable…

Thanks for the post PTP, but it’s not about whether or not I believe you, - I just don’t think we’re talking about the same thing.

Admittedly, I do find it difficult to believe that two men did all that work!

I would expect the first week to be taken up ripping out the existing stud walls, taking out kitchens, bathrooms etc, taking down ceilings, and filling a couple of skips. It would take 2 men all the next week to replace rotten timbers, put up the ceilings and wall boards while working around plumbers and electricians first fixing. Could it all be skimmed in a week by two men? I doubt it. Not if you skimmed each room completely and including the stairwell. I would expect the skimming to take two weeks for two men and a labourer. Then it would take one man a week to put in the bathroom ply floor, sanitary ware and to tile it. It can’t be done quicker. Then the second fix carpentry, the kitchen, repairs to the roof, putting down floors, cleaning out the waste, insulating the attic, scrubbing down for the painter… I can’t see it happening in 4 weeks. And what painter will paint a 2500 sq ft house for €500!

But if you were working on an old Period house while trying to save the original features it would be significantly slower, and significantly dearer. That was my original point.

So messing with those figures and trying to play ‘divils’ advocate, judging by those Uk prices, any double storey 100m2, or 1000 sq foot property below £150k/€170k is selling below building and finishing cost? This is not assuming any land cost is it?

Some conclusions: Either well priced Irish property is getting very close to it’s replacement cost, or UK construction costs/property are overinflated.

With an average age of a UK FTB of 38, I suspect the latter may be an issue.

It definitely has in many places. And in areas where supply exceeds demand it has gone well below replacement cost.

Labour prices have taken a huge hit, margin is pretty much non-existent, but materials (on average) have increased in cost.

Well… firstly 10 m² would be 32*32ft = 1024 ft². That’d be an awfully big extension.

But, yes, UK construstion costs are overinflated.

Incidentally, when viewing/bidding on a house you should always ask for a copy of the buildings insurance and a history of any claims.
This will give you the true (replacement) cost of the building and therefore its true value.