Planning a home extension, where to start?
Discussion
I'm looking for advice on best practices when it comes to planning an extension to my house.
I don't really no where to start, I would welcome the thoughts of other who have been through this process.
I'm looking to knock down an old conservatory which is attached to my kitchen, and replace this with either a single or double storey extension.
Size, at a guess around 4m X 4m.
With velux windows, patio doors, kitchen island, family lounge area, log burner etc.
If I add a second story, this would be to increase the size of the family bathroom above, the bathroom wouldn't necessarily need to come out quite as far maybe 2m x 4m.
The larger bathroom isn't a must, it will depend on how cost effective it is.
I'm also looking at replacing a spiral staircase with a modern traditional staircase, this leads to an old loft extension, which isn't currently used as a bedroom, this room has an ensuite already but I'd like to remove that and make the room bigger, this I hope would also allow for the new staircase.
I'm also looking at changing the house from its current 5 bedroom to a 4 bedroom by turning, the smallest bedroom into my ensuite shower room for my bedroom on the first floor.
If the budget stretches far enough, I want to knock down my current double garage and build a new one in a different location, either a timber framed garage, ideally with an upstairs room, doesn't have to be a habitable room for living, more a large storage area so the main areas of the garage can be used to park a car, motor bike and tinker doing man stuff.
Or a single story double garage made of timber or brick.
I have ideas but not a clue where I should start or how I should pay for this.
Should you instruct an architect, how much should you be expected to pay for this service?
What's the best way to fund such a project, pay outright, remortgage, half and half or something I haven't thought of, sell a kidney or two!
How much do you think such a project would cost?
Any information, the PH experts can send my way will be greatly appreciated.
I don't really no where to start, I would welcome the thoughts of other who have been through this process.
I'm looking to knock down an old conservatory which is attached to my kitchen, and replace this with either a single or double storey extension.
Size, at a guess around 4m X 4m.
With velux windows, patio doors, kitchen island, family lounge area, log burner etc.
If I add a second story, this would be to increase the size of the family bathroom above, the bathroom wouldn't necessarily need to come out quite as far maybe 2m x 4m.
The larger bathroom isn't a must, it will depend on how cost effective it is.
I'm also looking at replacing a spiral staircase with a modern traditional staircase, this leads to an old loft extension, which isn't currently used as a bedroom, this room has an ensuite already but I'd like to remove that and make the room bigger, this I hope would also allow for the new staircase.
I'm also looking at changing the house from its current 5 bedroom to a 4 bedroom by turning, the smallest bedroom into my ensuite shower room for my bedroom on the first floor.
If the budget stretches far enough, I want to knock down my current double garage and build a new one in a different location, either a timber framed garage, ideally with an upstairs room, doesn't have to be a habitable room for living, more a large storage area so the main areas of the garage can be used to park a car, motor bike and tinker doing man stuff.
Or a single story double garage made of timber or brick.
I have ideas but not a clue where I should start or how I should pay for this.
Should you instruct an architect, how much should you be expected to pay for this service?
What's the best way to fund such a project, pay outright, remortgage, half and half or something I haven't thought of, sell a kidney or two!
How much do you think such a project would cost?
Any information, the PH experts can send my way will be greatly appreciated.
Edited by Milner993 on Saturday 13th January 18:43
Just hire an architect. They will typically offer you either just design, design and tender or full project management.
I had design and tender.
Although you think it’s straightforward, and I did, they have a knack for coming up with ideas that you won’t think of. Well most, we went to two, one of whom just recreated the idea we had and one came up with an original ingenious way of having everything we wanted which I’d thought was not possible.
As for paying for it I can’t really say what is best for you, probably it’s easier to pay yourself and then remortgage once done. But it depends on your personal situation. There’s cash availability, liquidity of your cash, ltv vrs mortgage rate etc to consider. Most people on this forum have either got half a mill sat in their current account or would use pay day loans… middle ground doesn’t seem to exist.
I had design and tender.
Although you think it’s straightforward, and I did, they have a knack for coming up with ideas that you won’t think of. Well most, we went to two, one of whom just recreated the idea we had and one came up with an original ingenious way of having everything we wanted which I’d thought was not possible.
As for paying for it I can’t really say what is best for you, probably it’s easier to pay yourself and then remortgage once done. But it depends on your personal situation. There’s cash availability, liquidity of your cash, ltv vrs mortgage rate etc to consider. Most people on this forum have either got half a mill sat in their current account or would use pay day loans… middle ground doesn’t seem to exist.
I’ve just gone through this last year. First step is an architect who will do options and give you planning drawings. I then used a quantitative surveyor to get a rough price to see if I can afford it which was really helpful! I could then cut back but more importantly give it to builders so I can get proper estimates and there’s no differences bar labour between the builders.
http://www.estimators.com/
http://www.estimators.com/
Start with an architect, ok perfect!
As for budget, I don't really know, as always the cheaper the better but I don't want to compromise on quality, I know that cheap and quality never go hand in hand so there will need to plenty of compromises along the way.
If got cash of around £130k and probably another £200k + in equity in my home, however I don't want to blow all my saving and would love to keep my total cost under £80k excluding the garage, I know this will cost at least 30k or more by itself.
As for budget, I don't really know, as always the cheaper the better but I don't want to compromise on quality, I know that cheap and quality never go hand in hand so there will need to plenty of compromises along the way.
If got cash of around £130k and probably another £200k + in equity in my home, however I don't want to blow all my saving and would love to keep my total cost under £80k excluding the garage, I know this will cost at least 30k or more by itself.
Mr Pointy said:
Where in the country are you?
It wouldn't be difficult to blow £150-200k on all that work to the house, excluding the garage, your house value could fall due to the loss of a bedroom & you might have Building Control issues getting the loft work regularised. What is your budget?
I'm east Anglia.It wouldn't be difficult to blow £150-200k on all that work to the house, excluding the garage, your house value could fall due to the loss of a bedroom & you might have Building Control issues getting the loft work regularised. What is your budget?
I had considered the loss in bedroom may mean loss in value, I've been battling with a better functioning 4 bed family home over a 5 bed house that doesn't flow quite right on the first floor.
Milner993 said:
would love to keep my total cost under £80k excluding the garage, I know this will cost at least 30k or more by itself.
I think you might need to multiply the those figures by 2-3 times depending on finishing quality. Our glazing costs were more than £30k!!But as everyone says, commission an architect whos portfolio is to your taste. The only way to really know how much its going to cost is when structural drawings are done and quotes come back from the builders.
Just be warned, once the architect comes up with something you really like it's very hard to bypass the design even if the costs are disproportionate. We could have done our build for half the cost if we had ignored the 'design' bit and just focused on functionality.
Edited by gangzoom on Saturday 13th January 19:35
I’m a building contractor in east Anglia and I’d imagine 2k a m2 would cover a basic build for a finished shell. May be tight due to the small size. Then if you add on anything ‘fancy’ bifolds etc. the log burner could add on considerably if you opted for a traditional masonry built chimney could add in the region of 10k by the times it’s done. Making a second floor small wouldnt necessarily make the build much cheaper may even cost more. By the time you’ve installed a beam of some type to carry the upstairs wall you’d still have the same amount of roof covering to do. You mentioned Velux windows but they may be a little tight to one end if you added a second floor. Also worth mentioning if it’s 4x4 the minimum a cavity wall could now be is 300mm so you’d be loosing 600mm on width.
Modern staircases can cost from £800 to £20000 upwards without making any structural alterations that would probably be needed.
A basic garage with attic trusses could cost in the region of £35k but again service lengths insulation boarding out etc could keeping adding on.
Don’t forget to design fees building control etc can soon add up to thousands.
Lastly on top of that you can add on 20% as builders tend to quote figures without vat
Modern staircases can cost from £800 to £20000 upwards without making any structural alterations that would probably be needed.
A basic garage with attic trusses could cost in the region of £35k but again service lengths insulation boarding out etc could keeping adding on.
Don’t forget to design fees building control etc can soon add up to thousands.
Lastly on top of that you can add on 20% as builders tend to quote figures without vat
Cliov6dan said:
I’m a building contractor in east Anglia and I’d imagine 2k a m2 would cover a basic build for a finished shell. May be tight due to the small size. Then if you add on anything ‘fancy’ bifolds etc. the log burner could add on considerably if you opted for a traditional masonry built chimney could add in the region of 10k by the times it’s done. Making a second floor small wouldnt necessarily make the build much cheaper may even cost more. By the time you’ve installed a beam of some type to carry the upstairs wall you’d still have the same amount of roof covering to do. You mentioned Velux windows but they may be a little tight to one end if you added a second floor. Also worth mentioning if it’s 4x4 the minimum a cavity wall could now be is 300mm so you’d be loosing 600mm on width.
Modern staircases can cost from £800 to £20000 upwards without making any structural alterations that would probably be needed.
A basic garage with attic trusses could cost in the region of £35k but again service lengths insulation boarding out etc could keeping adding on.
Don’t forget to design fees building control etc can soon add up to thousands.
Lastly on top of that you can add on 20% as builders tend to quote figures without vat
Thank you for your reply, have you any idea on how much I should be paying for an architect?Modern staircases can cost from £800 to £20000 upwards without making any structural alterations that would probably be needed.
A basic garage with attic trusses could cost in the region of £35k but again service lengths insulation boarding out etc could keeping adding on.
Don’t forget to design fees building control etc can soon add up to thousands.
Lastly on top of that you can add on 20% as builders tend to quote figures without vat
Chumley.mouse said:
I thought minimum cavity now was 100/150/100 ? 350mm ?
It depends on the type of insulation you use (among other things), but no, for extensions 100mm. cavity is still viable.** Edited to add: actually, for new-builds as well in certain circumstances, but that's going to depend on the SAP calculation, and on the design and specification overall.
Edited by Equus on Sunday 14th January 19:18
Milner993 said:
Thank you for your reply, have you any idea on how much I should be paying for an architect?
Most people seem to quote 5-10% total initial projected cost. Probably not far off what we paid, don't get confused with people that offer construction drawings based on what you ask for versus an architect, who should show you and challenge you on what you think the design should be. Laws of diminishing returns apply to some extent: a small extension doesn't take that much less effort than a large extension (we still have to survey the whole house, the Building Regulation/specification notes are pretty much the same level of complexity, etc.).
...Which obviously means that if you work on a percentage of build cost, it will be higher for a small project than a large one.
This is a graph of the old RIBA recommended fee scales (domestic work is the curve defined by 'Class 5', reflecting the fact that domestic clients tend to be the most time consuming, for any given project cost; at the other extreme, the 'Class 1' curve would be used for barns or industrial storage sheds, for example):
Note that not only are the curves steeper at the bottom end, the horizontal scale (project cost) is also non-linear, which means that the percentage costs are really heavily weighted against smaller projects.
I personally calculate our fees based on the number of hours we think a job will take, from experience, rather than using this graph, and most practices would discount from it anyway, these days (it also shows the fees for a 'full service' in accordance with RIBA project definitions, which domestic extension clients seldom use), but it will give you some idea.
...Which obviously means that if you work on a percentage of build cost, it will be higher for a small project than a large one.
This is a graph of the old RIBA recommended fee scales (domestic work is the curve defined by 'Class 5', reflecting the fact that domestic clients tend to be the most time consuming, for any given project cost; at the other extreme, the 'Class 1' curve would be used for barns or industrial storage sheds, for example):
Note that not only are the curves steeper at the bottom end, the horizontal scale (project cost) is also non-linear, which means that the percentage costs are really heavily weighted against smaller projects.
I personally calculate our fees based on the number of hours we think a job will take, from experience, rather than using this graph, and most practices would discount from it anyway, these days (it also shows the fees for a 'full service' in accordance with RIBA project definitions, which domestic extension clients seldom use), but it will give you some idea.
Edited by Equus on Monday 15th January 10:14
Mark V GTD said:
My 8% new house fee, I should clarify, is not for a private home owner as the project is a commercial development so much less client interaction.
Yeah, we do a fair amount of work for commercial developers designing both estates and new standard housetypes on multi-plot schemes; I've never tried to calculate it against development costs, but I'm sure it would be a small fraction of the cost of a bespoke design for a private client. Even then it's money for old rope... developers give give us a brief, we produce a commercially acceptable design, they pay us for it (eventually... their invoicing cycles tend to be on the slow side). It's easy money.Compared to the amount of client interaction and, franky, hand-holding that your average domestic client expects, it consumes very little time at all.
The work is much more interesting and engaging, and I love most of them to bits, but commercially domestic clients are a bloody nightmare!
Mark V GTD said:
I'm an Architect and just quoted a fee of 8% of build cost for a new house (£500k estimated construction cost).
Can I ask what you get for this?- Ideas of best layout
- Drawings?
- quantifies of materials?
- Any level of project management?
- Getting it through planning support?
Not challenging the fee but want to know the deliverables (As I am starting to think about a large extension)
Thanks
I think £2K per metre squared sounds about right, in my experience that will double by the time you’ve got the rooms finished and VAT paid.
Personal recommendations are a huge plus, go and visit houses they’ve recently done.
Most importantly, agree with your architect and builders that you won’t pay the last instalment, until you’re certain they’ve finished the job. My architect disappeared the moment we paid him, only for us to discover that he’d miscalculated regarding the structural beams required.
Personal recommendations are a huge plus, go and visit houses they’ve recently done.
Most importantly, agree with your architect and builders that you won’t pay the last instalment, until you’re certain they’ve finished the job. My architect disappeared the moment we paid him, only for us to discover that he’d miscalculated regarding the structural beams required.
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