One of the odd things about the UK property market is arranging the price brackets of houses by the number of bedrooms they have, rather then the overall area of the property, which is the way it’s done in most other countries.
This means that adding an extra bedroom can move your property into another price bracket like few other home improvement projects.
Extending Up or Out?
If you want extra bedrooms, it’s usually a straight choice between an extension and a loft conversion. But the trouble with an extension is that, unless you have a bungalow, you need to build two stories to get a ‘normal’ bedroom added, which increases the cost and the disruption to your daily lives.
A loft conversion can give you the extra bedroom with less disruption and lower outlay and you don’t lose any of your garden either.
Not all lofts are suitable for conversion though. If the roof is at a shallow pitch, you may not be able to get the legal minimum height without raising the roofline, a difficult and expensive job that may not get planning approval.
The other sticking point is that you may not have the space needed to get a staircase up to the loft, although employing an architect should get you access to some excellent problem solving skills for that one.
The basic work on an older house will involve strengthening the rafters to take the extra load, moving any plumbing and tanks out of the way, insulating the roof and putting in windows, either flat skylights or dormer windows.
Then the room(s) will be constructed with stud partitioning and plasterboard, doors and electrics put in, then decoration will finish the job off.
In a more modern house the roof supports are likely to be A-framed trusses, which will mean that the trusses will encroach on the roof space a great deal more.
This means that it will be a more expensive job, to cut out those trusses and replace the strength that’s lost with extra bracing.
It’s quite common to put an en-suite bathroom in a loft conversion if there’s space, making the new top floor into a master suite haven that’s separate from the other bedrooms on the second floor.
Planning and Regulations
A loft conversion will almost certainly involve planning permission and building regulation approval. If you are just boarding the room and putting a loft ladder in to be able to store boxes then you don’t need any permissions, but if it’s going to be any sort of habitable room, like a bedroom, then building regulations will be involved.
The things that the building inspector will be looking at are provisions for emergencies such as fire, correct structural modifications, sound and heat insulation and ventilation, and waste disposal if there’s any toilet or bathroom in the loft.
Again, an architect will help make sure your conversion is compliant.
In terms of planning permission, if other houses in the street already have loft conversions then it’s unlikely to be a problem.
The main issue will be the windows, what they look like and who they might overlook. In some cases, if you put in flat skylights, you may not need planning permission at all, although in Scotland you are likely to need permission even for that.
Remember that regulations often change and it is wise to check the latest regulations directly with your local planners.
Use Your Imagination
Of course, there’s no reason why a loft conversion should be a bedroom. With the right guards on the staircase it can be a children’s playroom, with a bit of soundproofing on the party walls, if you have them, it can be a music room.
With more and more people working at home, or needing somewhere to use a computer at home, it can be an office or study. Just let your imagination do the work.
Loft conversions give you a very good return on your investment but sometimes there isn’t the roof height at the apex, or width, to give you enough headroom for a usable space.
One option that can resolve this is a roof extension. This is where the roofline is extended to the outer walls of the house, a bit like a full width dormer window.
The Investment Potential of a Loft Conversion
Extending into the roof is one of the best projects for a renovation because you can add a bedroom (or two) and possibly a bathroom as well. Because of the way that houses are valued in the UK this will push your house up into the next price bracket.
But you don’t have all the building work required for an extension on the ground, like excavating for foundations, drain re-routing, then building the foundations, walls and ceiling. There may need to be some strengthening work done to the loft floor and some re-jigging of roof supports but that isn’t anywhere near as labour-intensive and expensive.
All you then need to do is put in stairs and dormer windows or rooflights. The rest is interior fitting and finishing which you would be doing with an extension on the ground anyway.
Roof Extension Economics
If your loft isn’t the right size or shape for a traditional loft conversion with dormer windows or rooflights, then you may still be able do it but the line of the roof will need to be pushed out to give the headroom first.
The cost benefits do change if you have to do a roof extension though, as there is a lot more work to be done.
Assuming you are starting with an apex roof, pushing the roof line out will involve taking away the rafters on one side. New side walls are built, an end wall with a window and then a new flat roof over the top.
There needs to be additional support too, to replace the strength lost from the removal of the rafters.
This is a lot more work than a loft conversion on it’s own, and that means more expense. It will almost certainly require the hire of scaffolding to the highest storey, and it means a lot more material coming up through the house or up the scaffolding.
Although the cost is greater, for probably little tangible extra return, if the alternative is a loft conversion with very low headroom which could put off potential buyers, the bullet simply has to be bitten.
Planning Issues for Roof Conversions
Anyone taking a train through the suburbs of any major city in the UK will be able to see why planners aren’t that impressed with the majority of roof extensions.
You will be able to see row upon row of houses built between 1850 and 1940, all with roof extensions of varying degrees of quality and beauty.
For this reason very few houses will get planning permission to put a roof extension on the front of a house. At the back there will be more leeway, especially if many other houses in the street have had them built already.
Before making any plans it’s essential to speak to the planning department, or an architect with previous loft conversion experience in the area, to gauge your chances of getting planning permission.
The most critical point abut a roof extension is to make sure it is all structurally sound. It is utterly essential to get the opinion of a qualified structural engineer as the weight of the roof supports will add to the weight of the new floor supports and fixtures and fittings, not to mention the people using the room.
You can be more creative with a roof extension too. Even if you have the room for a decent loft conversion, a roof extension can open up more possibilities. For example if you aren’t overlooked you may be able to have patio doors and a terrace on the roof – now that would really make a property more attractive.
Plumbing for a Bathroom in a Loft
With the increasing popularity of en suites it’s common to put a bathroom or shower room in a loft conversion too.
Adding a Bath or Shower
It’s not actually necessary to have a bathroom in the loft, just a toilet and a washbasin would be a great help. But of course fitting a bath or a shower in, to make it a proper en suite, will make it that more useful and add more value. The problems are, of course, with space.
A bath will take up a lot more floor space but at least the end of a bath can use areas where the headroom is restricted. You also have to be sure that you can actually get the bath up the stairs to the new en suite! A shower will take up less space but has to go where you have full height, in the centre unless you are extending the roofline out.
Extending and Plumbing
The key to making the plumbing simple for a loft conversion is to site the bathroom as a close as possible to the existing waste and supply pipes. This will make it easier, and therefore cheaper, to install the new en suite. Fortunately this is usually at the rear of the house, sometimes at the side.
If you are building the roofline out then you are unlikely to get planning permission to do it at the front, it will almost certainly have to go at the back. This will hopefully put the toilet and bath or shower in the right place to make connections to existing plumbing reasonably straightforward.
Dealing with Waste
This is particularly true of the waste pipe as it is wider, so it’s more difficult to get the pipe around corners. There needs to be a certain fall (gradient) along the length of the pipe too, to ensure that the waste flows out properly. You really need to avoid having to put in new waste pipe from the loft conversion if at all possible.
It’s not impossible but you then also have to excavate to link the new waste pipe into the correct drain. All of this adds expense. As the beauty of a loft conversion is that it adds maximum value to the property for the minimum outlay, extra expense should be avoided.
Using Micro-bore Pipes in a Loft Conversion
There is another solution to this problem though. Laying micro-bore plastic pipes from the new toilet to the existing waste is easier than with a traditional waste pipe. You need to add an electric macerator to the waste pip of the toilet; this grinds the waste down so that it is small enough to pass through the small-bore pipes. They often include a pump to push the waste out as well.
Take care with the plumbing layout though, as the plastic pipes don’t like 90 degree bends. Keep any bends to 135 degrees and you should be fine. This may need some lateral thinking to fit your layout but trunking and boxing-in can hide a multitude of sins.
Pushing Water up to a Loft Conversion
Getting water supplies up to the new en suite is a breeze after all the palaver with the waste. An electric shower with a pump will work well and there’ll be no messing about trying to fit a header tank into the restricted roof space left after the loft conversion is done. Mains pressure should be enough to push cold water to the toilet cistern and basin, the only thing you then have to resolve is hot water to the basin.
You might be lucky and find that there is enough residual pressure to drive water up to the loft from the hot tank, but it’s unlikely and you’ll probably need a plumber’s advice to find out first. You can install a small pump, which will be noisy, or an instant water heater over the basin, which will look naff.
If you have a combi boiler (which heats water instantaneously rather than heating a tank) you are more likely to have success getting hot water up to the basin without resorting to one of these undesirable solutions. These are designed to push hot water upstairs from a boiler in a kitchen or utility room so they may well go the extra mile.
Don’t Forget Ventilation
Regardless how you solve the plumbing problem, don’t forget ventilation. You may not be able to get a window in the bathroom area so an extractor fan is the best bet. This has the advantage that it will come on whenever the light is turned on, whereas you can’t always rely on people to open the window, particularly in winter.