LIST OF SELF-BUILD QUESTIONS ANSWERED IN THIS ARTICLE:
– Are permitted development rights removed when you do a self build?
– Is there a limit on the height of your building? Are you better to go for a smaller footprint with a higher roofline or a larger footprint with a lower roofline?
– What are the plot investigations? Who do you ask to get them?
– How many inspections by a quantity surveyor will you expect on a standard build? How much would you expect to pay for a visit?
– How much should you expect to spend per metre square for SIPS?
– What is the comparison in terms of longevity between SIPS versus brick and blockwork? Which one is more eco-friendly, and which one lasts the longest?
Permitted development is usually removed in areas where the council or the planners might think that you’re pushing the boundaries of overdevelopment. They don’t want you to come back with lots of larger extensions and add-ons once you have gone through the process.
Therefore, unless it specifically states in the conditions of your planning approval, you will have permitted development rights. If it is listed building or conservation area, these rights are usually removed. The easiest thing to do is to perform a Google search for listed building and then your local planning authorities name and you’ll get their guidance on it.
It is important to understand that permitted development rights only come in once the house is complete. So, there are no permitted development rights for the house during construction. Once it’s finished and signed off, you can then go back and add in new structures or outbuildings.
I would also recommend checking the guidance. It might be that if you’re still going through the process, that you could do a minor material variation or non-material variation to the planning application, and deal with it that way. You can also wait till construction is finished and then do a certificate of lawfulness application to get confirmation that it has permitted development rights.
If you are on-site and want to get it done as part of the building regs exercise (or building warrant exercise in Scotland), you may have trades on-site and want the work done at the same time, so go in with an amendment to the planning application. This way you can cover all bases and prevent any issues.
It depends on the constraints. If you are building in a back garden or you’re replacing a dwelling, and you’ve got houses either side or you’ve got an existing house, then they’ll probably fix the ridge height. Usually, the ridge height is based on the neighbouring properties. We can usually push that plus or minus half a metre.
If it is a fresh plot of land that you are building on, and there are no real constraints, it will be down to the planning policy. There will be a design guide, a neighbourhood plan, or a local development plan that will stipulate all the considerations that you need to take into account while building.
If, for example, you are building in rural Scotland, they’ll probably want it to be one and a half storeys, because that is the traditional type of housing. If your plot is in the middle of nowhere with no impact on the surroundings, then you could push to two or three storeys.
The best thing to do, from day one, is to have a chat with the planning authority or speak to an architect. To summarise, if there are buildings around you, they will dictate or guide the height. It is up to you and your architect to make a planning case.
If you are working with an architect who does CGI’s and photorealistic images that show the project in context and has a good design, then you can usually achieve more. It’s all about communication with the planners.
WHAT ARE THE PLOT INVESTIGATIONS? WHO DO YOU ASK TO GET THEM?
Soil investigation is key. It is crucial to make sure that the ground can take sustainable drainage systems and you do it by performing a percolation test. If you’re not connecting into the mains sewer for foul and surface water, then you need to deal with it on site. The surface water usually goes into something called a soakaway that drains either into the ground or it goes to a stream. The ground needs to have the right percolation rate to do that. That also applies for having a sewage treatment plant or a Klargester to deal with the foul.
The other things are services. For electricity, if you get a quote for over £30,000, consider an off-grid connection. For between £20,000-£30,000, you can get a stable off-grid connection with PV, hot water, renewables and some form of generator backup.
If you’re buying something that’s got outline planning or full planning, make sure that you can deal with the conditions. When planners put conditions on approvals, it doesn’t necessarily mean that you can meet those conditions. They’re just conditions that they need to be able to satisfy the guidelines. It could be something like creating new access to make sure you’ve got the visibility splays. It is your requirement, and you have to make sure that you can satisfy the conditions. It is really important not to presume, just because it’s got planning, that you can satisfy those conditions, both in terms of physically or financially satisfying them.
If you have an old building or there are trees or you are near a watercourse, you’ll need to have some form of habitat studies, whether it’s bats or birds. These can only be done at certain times of the year.
These are the key things that can often cause big delays in getting planning validated or planning approved.
And finally, do not speak to anybody without knowing what your budget is and where it’s coming from.
It depends on what route you’re going down. If you’ve got a quantity surveyor involved, you’re probably going for a more professional building contract. Usually, one of the GCT contracts where you’ve got a QS managing the cost, and you’ve got an architect or another professional managing the contract administration side of your build. This isn’t done by everybody, but a lot of people will do that to keep a real tight control over cost.
It also depends on the way that the contract is administered. It may be at every point when your builder wants a stage payment, your QS will need to visit the site to value or check the works.
Some QS’s will budget £300-£500 per site visit, or it will be done on a percentage of construction costs split over the term of the contract. A one-off house could be anything from 24 weeks to 12 months depending on how it’s going to be built, and that depends on the project. We work with a company called CLPM, who are really good self build specialists in terms of QS project management, and they’ve got a lot of useful information on their website in terms of blogs and advice.
Some self builders will just do it all themselves and they’ll not have a QS involved. They’ll trust the people they are working with, they will get valuations and they will pay the bills.
Larger projects that are managed more professionally, will have a QS project manager and somebody dealing with contract administration.
I’m sorry that I can’t give an exact answer to that. But speak to some QS’s, get some fixed quotes and then just take it from there.
HOW MUCH SHOULD YOU EXPECT TO SPEND PER METRE SQUARE FOR SIPS?
It depends on the efficiency of your build. The raw timber material starts its life as a certain size. So, if you’re keeping within those sizes, and being as efficient as possible, for a storey and a half or two-storey house you would pay the minimum of around £250-£300 per square metre. That’s for a two-story build of approximately 250 square metres or above.
The smaller the build gets, the higher the cost per square metre. This is because you still got the same factory overhead and costs. If you’re doing a single storey building, that £300 per square metre could become £500 per square metre, because you still need ground floor walls and roof, but not the intermediate floor on the first floor.
Again, there are massive differences in terms of efficiency, design, size and type of panel. Comparing a rectangular building and an H-shaped building with the same floor areas, the H-shaped building could cost 30% more, because you’ve got more angles, more turns, more cuts, and far more linear meterage of product.
WHAT IS THE COMPARISON IN TERMS OF LONGEVITY BETWEEN SIPS VERSUS BRICK AND BLOCK?
There will be far more embodied energy in the timber. The core process of creating the timber frame or SIPS, as opposed to the energy that’s required to create the cement and the brick and block. Lifetime cost and performance, timber frame or SIPS will outdo brick and block.
SIPS buildings have been built in the US for 40 or 50 years with no significant failures in terms of degradation of panels. In the UK, it’s about 15 or 16 years since the first SIPS building was erected. In terms of standards, buildings are built to last about 20-25 years, so SIPS by far exceeds that.
You can find out more about longevity in this article here.
