Q: How much does a house cost to build per sq foot?
A: This must be the most debated topic outside of ‘Brexit’ and rising property prices in Ireland.
A good analogy is to think of what a car costs per square foot. It’ll depend on whether it’s new or second hand, a people carrier or a German luxury sports car, whether it leather seats, two doors or four. It is the very same for building. Almost every house is different, some have double glazed uPVC windows, some have quadruple glazed aluclad. Some have red deal floor boards some have American White Oak wide plank solid flooring. Some have fibre cement slates on the roof, some have copper or zinc.
In this context, a bog standard house could conceivably be built for approximately €80 per sqft plus VAT but this is for a simple design (rectangular, plaster finishes, fibre cent slate roof, double glazed uPVC windows) with no finishes (tiling, flooring, decoration, patios perhaps not even a kitchen sink!).
In NI you can claim VAT back so while the figure is around the same mark it excludes VAT. There are many examples of this type of house scattered in housing estates throughout the 32 counties.
Q: What drives up the cost per square foot?
A: As a general rule, the more complicated the design, the more expensive to build. More elaborate houses have more irregular shapes meaning more insulated external walls, more structural steel, more roofs, more tricky areas to weatherproof and finish, etc. Site conditions are also important. Is the site on a slope? Is it well drained? Is there rock in the ground? Do the foundations need to be piled?
Q: What about extensions?
A: Extensions will command a higher cost per square foot and are much more difficult to pin down but certainly well over the €100 / £80 plus VAT mark. In NI extensions are not VAT exempt. Costs can quickly rise with issues surrounding restricted access, demolition and propping, tricky detailing to connect the house and extension, drainage and service diversion, to name a few.
Selfbuild Live Cork is the ultimate showcase for people who are building, extending, improving or simply decorating their home. Selfbuild Live Cork, 9th & 10th November takes place in the Green Glens Arena, Millstreet, Co. Cork.
Q: Why are my tender prices coming in at different rates?
A: Builders will price projects differently – some may use previous experience, others may employ a quantity surveyor. They may add a percentage to factor in risk factors which could price them out of the running. Sometimes they get it right, sometimes they don’t. Remember that a building does not cost the original estimate quotation, but the final account. So tender drawings and construction details are essential to get comparative quotes.
Don’t be lulled into a false sense of security, get the tenders in for the spec you want to see where you stand. And remember, if a quote looks too good to be true, it probably is. You do get what you pay for.
**UPDATE September 2019
Update from quantity surveyor Keith Kelliher:
“It’s fair to say that very few people (who are paying legitimate) are getting their shells done now for less than €100-120/sqft.”
“The RIAI are now quoting figures of above €200/sqft for a finished house. I would much prefer to change the narrative around approaching the idea of cost from the right way which is to get a sketch plan drawn and then get a budget estimate done for that design.”
“I don’t agree with the idea of cost per sqft as it just has no accuracy and takes no account of any particular design.”
— Keith Kelliher of quantitysurveyor.ie
“To update this article, I would change the ‘bog standard’ figure from €80 to €100-110 per sq foot plus VAT.”
“Extensions are really too difficult to project and a little meaningless as extension design has changed from the standard ‘sunroom’ extension of old to an architect designed parapet roofed extension with significant glazing steelwork, demolition etc., so there is no real basis for cost per square foot analysis particularly with reference to extensions in the past.”
“I also agree with Keith’s comments above.”
— Kieran McCarthy of kmchomes.ie
SelfBuild Ireland has just launched a range of build cost calculators powered by online budgeting tool ProntoCalc. The Build Cost Calculator gives you a rough idea of how much your project will cost, contractor led. It’s free, quick and easy. You can use it below:
9 comments
can you please give me estimate o f building 173sq metre timber frame house.
1 an 1/2 storey. with very good insulation
Drilling down into the detail is what will give you an accurate costing but we do have a free calculator to give you a ballpark figure as well as a more detailed tool available here: https://selfbuild.iebasics/calc/ Best of luck with your project!
hi Is timber frame more expensive to build than masonry wall?
Hi Sarah, it depends on how good a U-value you want to get, generally speaking from what self-builders tell us masonry tends to be cheaper but when you factor in insulation and airtightness nowadays it tends to be on par with timber frame. Generally you’d be pricing up both options for the spec you want to compare like with like; you could also ask the self-build community on facebook to get other self-builders’ opinions: https://www.facebook.com/groups/417770178588456/
Hi if I were to buy a house 1 storey and then add a 40sqmt extension what kind of price do you think this would be?
There are too many variables to give an accurate cost figure, quantity surveyors (cost consultants) tell us it’s vital to have an idea of what the design will be as well as how you plan to build it to get a ballpark figure for the build cost – remember too that there are other costs to consider including design, planning/building control/supervision, connection fees (water, wastewater, electricity, broadband) and general council fees. Generally speaking extensions tend to be more costly per sqm than a new build but that depends on the project. You can check out this cost calculator for a very rough figure: https://selfbuild.iebasics/calc/
Hi, we have been given retention for our 3 bed log house but have certain stipulations to follow:
1st we have to tie into the original family cottage with an extension area of 20m2.
2nd we have to raise the roof profile to accommodate the tie in (the original metal roof stays put). We plan to use 600×300 composite slate.
3rd we have to slab the outside of the log house with cement board (Permabase Cement Board etc.,).
The floor area of the log house is approx 100m with a small “L” one end (3mx6m).
Can you give me approx. costs for extension and the wrap separately please.
Thanks in advance, Pat
Hi Pat, Selfbuild organises events, publishes a magazine, and curates online content. We don’t do any building work or provide costings; you might want to either contact some builders or a quantity surveyor for that kind of information. Hope this helps, Astrid
I have been making enquires, to reply to Pat Grant, i was looking about planning in Meath, for log cabin, absolute nightmare, anyway one option that was sugested to me was, to wrap with board and render, but the cost was up to €10,000 on a 700 square foot cabin, hope that helps.