At the very beginning of the loft conversion, in the ‘ideas’ stage, after the ‘let’s make the loft into bedrooms’ thought, there will be the plan to build some stairs from the current landing into the loft.
The design considerations of the staircase is possibly the main piece you have to get right. Planning rules and regulations for staircases are very specific and could force you to alter your ideas of where you can situate your new stairs.
Strangely, despite the importance and design rules of the staircase it’s normally one of the later jobs to be started during the loft conversion. Opening a big hole in the ceiling is going to be very messy so it’s normally left until later, after the new loft floor, insulation and stud walls have been completed.
Existing stairwell design
In the vast majority of cases the existing stairwell in the best place to start thinking about situating your new stairs to go up into the loft. Using the existing stairwell and appropriate fire doors gives you the protected stairwell the local planning people will insist on before they will approve your plans.
The common design layout is where there is a box room above the current stairs which lead to the landing. Depending on the size of your landing area, and of course your preferences, you can leave the box room alone and start with a couple of steps from the landing to a small platform and then turn 90′ and continue the rest of the steps over the current stairs into the loft.
Head height in the loft
One very important thing that needs considering is the head height allowance in the loft where the new stairs will emerge. You will need at least 2m clearance to the new ceiling (i.e. after the insulation and boarding has been fitted).
Terraced and semi-detached houses normally have the stairs against the wall to the neighbour, so head height isn’t normally a problem in this case, but it’s such an important issue it’s worth checking and double checking.
What to do if there’s not enough head height.
Having a sloping roof above your stairwell means you’ll have to seek some creative options for your new stairs, so they come out into the loft at a suitable place where head height won’t be a problem.
You may have to turn your stairs at a right angle, taking some space from one of the two larger rooms. It’s imperative there’s enough head height in the loft where the new stairs will end. You’ll need a minimum 2m head clearance across the full width (800mm) of each step.
As described previously most homes will be fortunate to be able to run a new flight of stairs over the existing landing or losing the box room at the front and taking the stairs in a straight line.
Modern homes tend to be more compact, and with smaller rooms comes smaller loft space and less head height. If this is the case and you can’t fit a traditional style staircase then you will want to look at installing a spiral or compact staircase.Professional loft convertors would be able to advise on the type of stairwell.