Your Building Dilemmas Solved
Looking for expert advice on your project? Our team are here to answer your need-to-know questions. This month, the experts tackle removing internal walls, package builds and choosing between pitched and flat roofs
From removing internal walls, extensions and package build companies, our experts solve your building questions
I’ve been looking into package companies and have heard the term ‘turnkey’. Whatdoes this mean and how do i decide whether it’s the route for me?
OLIVER GRIMSHAW SAYS: In a nutshell, ‘turnkey’ is a term given to a completed product. What constitutes a completed product could possibly be open to interpretation among various package build companies. At Hanse Haus, for instance, when a client instructs us to build a turnkey property for them we commit to delivering a house which is ready to move into.
Although it always depends on the internal fit out and architectural design – both of which are determined according to individual specification – the estimated cost of a turnkey house is approximately £1,500/m2. This price includes everything from floor covering, tiling, staircase, internal/external doors, and all plaster finishes, to paintwork, sanitaryware, skirting boards, internal window sills, electrical work, plumbing and underfloor heating, as well as a heat recovery system.
The only thing we stop at is the kitchen – giving our clients the run of the market – although we work closely in coordinating with chosen kitchen suppliers. Bear in mind that most package companies do not undertake the groundworks, foundations and service connections. However, we do work with and have longstanding relationships with groundworkers to deliver this aspect of the build.
Our turnkey service allows us to manufacture and complete a project according to our clients’ preferred standards. That includes building to any level of energy efficiency (as long as that level is high!), and also finishing the house with almost any external or interior features requested. The Hanse Haus sample centre in Germany, for instance, is home to thousands of interior and exterior fittings from which to choose from within the turnkey option — with brand names such as Villeroy & Boch, Huppe, Hansa, Velux, Duravit, Hansgrohe and many more on offer.
Turnkey homes undergo countless external and internal quality checks, and the benefit of a site foreman and project management service means that there is always someone responsible for overseeing quality control. In terms of whether it’s the most sensible route, self-builders looking to protect themselves from unexpected costs and those seeking overall peace of mind when it comes to quality would likely find the turnkey option their preferred route to building their dream home.
Wearereplacingourold flatroofextensionwitha new, larger addition, but we’re undecided on whethertostickwithaflatroofor go for a pitched roof design. How canwebesureapitchedroofisthe bestchoiceforourextension?
A HUGO TUGMAN SAYS:
Pitched roofs are the most common form of roof for UK homes. Almost all roofs are actually sloping, but any roof with a slope of more than 5° would be considered pitched, and any with a slope of less than 5° is considered flat. Pitched roofs are typically formed with timber rafters (joists on a slope) thataresupportedonthewallsofahouse, with furthersupportfrompurlinsandtrusseswithin the roof space. A waterproof roofing felt is laid over the rafters beneath horizontal timber roofing battens (regularly spaced small strips), which in turn support roof tiles or slates.
If you are extending a house with a pitched roof, very often a matching pitched roof over an extension can be the most pleasing form. However, it is important to try to keep to the same pitch angle, otherwise it can look incongruous. (Although, a matching pitched roof isn’t the only way to stay in-keeping.)
You’ll need to consider the height of your extension too. If you are proposing a pitched roof that slopes away from the house (often known as a lean-to roof), then height could be an issue. Assuming youmatch the pitch angle ofthemainroofandyouhaveaheightofatleast 2m at the lowest point, then, depending upon the depth of the extension, you may find the roof would hit the house above the first-floor windows, so this needs careful consideration.
The roof overhang in relation to the boundary will also influence your choice as to whether a pitched roof is the best option. The moststandardfeatureatthelowestpointofthe slope (or eaves) is for the roof to overhang the wallbelow and there tobe a gutter on the edge. If you are extending right up to a boundary, however, youwould actually need to build the extension wall well inside the boundary line so the roof edge doesn’t overhang your neighbour’s property. Unfortunately this will reduce the usable space inside. Away to avoid thisistouseaslightlyraisedparapetdetailwith a box gutter behind.
When you’re extending close to a neighbouring property, the height at the boundary is crucial too when it comes to gettingplanningpermission passed. Aparapet can raise the wall height, so you must think carefully about what design you have for the junction where roof and wall meet, and perhaps consider getting an architect to help with a specialist detail such as cutting a slot gutter into the edge of the roof.
Generally speaking, pitched roofs tend to be a more expensive choice than flat roofs – usually by 20-30% – as they require more work andcostliermaterials. Forexample, ifyouwere building a modest flat-roofed rear extension, with a construction element in the region of £20,000, probably about £4,000 of that sum would be for the roof. With a pitched/tiled roof, it might be roughly another £1,000 or £1,500, as it would require more timber, more labour andmore expensive roof finishes (tiles or slate rather than EPDM rubber roofing or GRP fibreglass roofing).
“Generally speaking, pitched roofs tend to be a more expensive choice than flat roofs — usually by 20-30%”
I’m renovating a 1970s detached house and looking to open up my homebyremovingsome of the internal walls. How best do I go about this?
JASON ORME SAYS:
Opening up spaces in older homes is becoming more common, and while it’snotparticularlydifficult, itneedsapproaching correctly— notjusttoensureyourhomedoesn’t develop an alarming lean, but so that you maximisethebenefitsofopeningupthespace.
You can typically remove any internal wall — supportingorstudpartition. Theimpactithas ontherestofthehomeandtheamountofwork you’llneedtocarryoutdependsonwhetherit performs a structural function or carries the weight of any walls above. Removing a loadbearing wall will cost more and require more in the way of associated works (such as adding in piers and beams to ensure the structural integrity of the home).
However, from a design point of view, it shouldn’tputyouoff. Oneofthemostcommon forms of domestic building projects in the UK – the side-return and rear extension – relies on structural walls at the side and back being removedandreplacedelsewhere. Sodon’tstart from the position of worrying about loadbearing walls — that’s what structural engineers are paid to do.
Depending on the scale of the job, you will probably have engaged either a builder or a designertoassesstheproject. Ifit’sjustknocking through to turn two rooms into one there isn’t a lot of design work involved and you might workdirectlywithabuilder. Ifit’spartofalarger remodel, a designer is probably the best place to start. Either way, the next step you should takeistoengageastructuralengineer. Theyare the best people to evaluate the walls and the role they play, and whether they are nonloadbearing or loadbearing. Your builder or designer will probably be able to recommend someone they have used previously.
Non-structural walls can typically be removedwithoutanycompensatingmeasures being necessary, bar making good the walls, ceiling and floor.
If you’re removing loadbearing structural walls, youwillneedtoinsertabeamtosupport what is above it instead. This is usually steel, and the structural engineer will calculate the depth and width of the steel beam needed to hold the weight. They will also calculate the positionsofanypiers(anuprighttosupportthe beam, like a goalpost) and associated works.
The larger the span of space the steel beam is required to cover, the bigger the depth of the beam. Thiscansometimesresultinitprotruding intotheroombelow— usuallyreferredtoasthe downstand. At this point, you might want to consultwithyourstructuralengineertodiscuss ways in which it can be hidden — preferably, in thefloorstructureabove. Thiswillnotonlygive you valuable inches in terms of head height, it will also look better.
For a ‘typical’ opening up project involving the removal of a 5m-wide loadbearing wall, builderswouldtypicallyquotebetween£1,000 and £2,000 (plus VAT, where applicable). This would cover the temporary support of the structure, demolition of walls, building of required padstones and supports for the new beam, insertion of the beam, plasterboarding out, and making good at wall, floor and ceiling junctions.
“Non-structural walls can be removed without any compensating measures being necessary”