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--- layout: post title:What headroom do you require over a loft stair. path:What headroom do you require over a loft stair. categories: section: post ---
The Building Regulations require that you maintain a clear headroom of 2000mm on any access between levels, which includes staircases. That includes loft staircases, spiral stairs in fact any staircase. Headroom has to be maintained while ascending the stair and also on the landings at the top and bottom. People are always telling me that on a loft staircase you can reduce it to 1900mm but I disagree. If you look at what part K 1.10 of the English and Welsh Regulations actually says, you will see a nice diagram that really defines it quite clearly. It basically says that in a loft conversion where there is not enough space to achieve the 2000mm headroom you can reduce it to 1900mm in the centre of the width of the tread. But the diagram shows a sloping ceiling which has a minimum of 1800mm at one side of the stair and 1900mm in the middle, by implication you would then have 2000mm on the other side of the stair.
This relaxation of the normal 2000mm headroom therefore only applies to a sloping ceiling in a loft conversion,which is over the staircase. It does not allow you to reduce the headroom to 1900mm over the whole width of the stair, it has to be a minimum of 1800mm at one side and 1900mm in the middle.
The Loft Staircase Doctor
--- layout: post title: What does a Genius spiral stair fix to at the top. path: What does a Genius spiral stair fix to at the top. categories: section: post ---
I am amazed at how many times I get asked this question, I suppose it is not that obvious, a lot of people assume that the centre pole will go right up to the landing ceiling and fixed to the rafters above. The reality is that a spiral staircase like any other stair normally ends at floor level and all that projects above the floor is the balustrading, which is there to stop you falling back down the hole.
With Genius spiral staircases and in fact all other kit spiral staircases that I can think of there are really only two main fixing points to the structure of the building. The first is a circular base plate on the bottom of the centre pole that is bolted to the floor. Then the top of the pole is secured to the vertical face of the ceiling aperture via the top tread that normally being a landing triangle. The landing triangle is bolted to the centre pole at one point of the triangle, the the opposite side of the triangle is butted up to the edge of the floor and secured with angle brackets underneath to the timber trimming or trimmer joists surrounding the opening. If it is a concrete floor slab or even a wall you would use the same brackets but different fixings.
The two fixing positions described above are all that is needed to hold the centre pole rigid. All the treads are simply attached to the centre pole. If the spiral staircase has any walls surrounding it is also advisable to attach brackets between the wall and any tread that passes it. These are not a necessity but they do help prevent any slight lateral swaying movement that is always likely to occur on spiral stairs.
The Spiral Staircase Doctor
--- layout: post title:Do kit staircases need any adjustment after installation. path: Do kit staircases need any adjustment after installation. categories: section: post ---
Theoretically once installed modular kit spiral and flights stairs do not need any real maintenance or adjustment. However it is my belief that most will need a re-tightening of nuts and screws at some point in the first year of its life. The reason for this lies in the moisture content of the timber components. Timber is hygroscopic, it tends to absorb or lose moisture due to the temperature and humidity of its environment. Unfortunately it will also tend to change in shape if you add or reduce its moisture content. Joinery manufacturers have long been aware of this and will attempt only to fabricate with timbers of a known moisture content. Joining two pieces of wood together with different moisture contents will cause problems when they eventually stabilize in their permanent environment.
Reputable modular kit stair manufacturers will make sure that their timber elements leave the manufacturing plant at a nice stable moisture content of around 10%. The problems start when the staircase reaches site. If it is a new build the environment it will almost be certainly be unheated and damp due to the tonnes of water used in brick,plaster and concrete construction. So the timber elements of the stair will increase in moisture content and size. Once the building dries out the timber elements will lose moisture content and shrink a little. This will cause any screwed or bolted joints in the stair kit to ease a little and create a bit of unwanted movement in the stair structure. The solution is is tighten up the fixings.
Ah but what about the nice stable environment of an existing property I hear you say. True there will be less of a problem apart from when you have to turn up the heating in winter. This has the potential to loosen joints the same as a new build property. In my experience it is a good idea to consider re-tightening all fixing after the first heating season, this will pay dividends and will probably only need doing in the first year.
The Staircase Doctor
The answer is yes you can, but with great care. In an ideal world you would have made provision for the Klan spiral staircase baseplate at the installation stage of the underfloor heating. By that I mean that you would have left an area at the centre point of the stair approx 500mm x 500mm with no heating pipes or electrical cables in it. However it is not a perfect world so a different approach is needed if the floor is already complete..
There are two basic problems to overcome if you are trying to fit a spiral staircase over an existing solid floor with underfloor heating in it. First you must not at all costs drill a fixing hole into a water pipe or electricity cable. Secondly you have to make sure that the baseplate of the spiral staircase is not sitting on anything compressible which will cause the stair to move. Bear in mind that the 200mm diameter base plate of your 200 kgs. Klan spiral stair has to take not only its self load but also your 150kgs granny as she wanders drunkenly up the new spiral staircase. Modern construction requires an insulation layer somewhere in the floor construction, this normally will have something like a 75mm concrete screed over it; this being adequate to take all normal loads without compression. However a point load like a spiral stair may need considering.
Solutions to both of these problems is really a matter of common sense. First you need to know the details of the floor construction so that you are aware just how just how deep you can drill, and the amount of compression that is likely. If there is no floor finish on top of the screed I personally would consider carefully breaking up the screed around the area of the base plate and shoving any pipes or cables out of the way if possible or at least marking their position if not. I would also remove any under screed insulation for a small area directly under that baseplate. The floor would then be re-screeded including the area of removed insulation. Once this has cured you can mark the runs of pipes or cables on it, so that you know where you can drill. Assuming that this is not on, then alternately you will need to replace any supplied expansion bolts with shorter alternatives that you can be sure will not penetrate the screed. This will of course not help the compression of insulation problem, which may not be a problem anyway. Should you decide it is, then your options are limited to digging it out as above or spreading the load over a greater area by forming some form of plinth under the spiral stair. Bearing in mind that this will affect the overall height of the Klan spiral stair. A customer once suggested that rather than sit the stair on his wood block flooring he would sit the base plate down on the screed and carefully cut the wood block around it. This would prevent any lateral movement of the baseplate without any further fixing needed. I am not sure I could totally recommend this action but preventing lateral movement is for sure half the battle of fixing the baseplate.
In conclusion do not be put off, a Klan spiral staircase will look good and function well, and in my time I come across a great many spiral stairs that have been fitted on top of underfloor heating systems without any problems.
The Spiral Staircase Doctor
The luxury Berlin space saver stair is by a mile the nicest looking alternate tread space saving staircase on the market. Unfortunately the wrap around stainless steel balustrade system can have problems meeting the Building Regulations. It is not alone in this, most wrap around wire or rod balustrade systems struggle to meet the 100mm sphere rule and can be considered too easy for children to climb. This is a pity because the wrap a round systems on staircases such as space savers or spirals look good and are very much in vogue.
You must also bear in mind that no alternate tread space saving staircase automatically complies with the Regulations, it all depends on what they are used for. In England Wales Northern Ireland and the Republic you can basically use them to serve one bedroom and an associated bathroom, although there are other conditions as well. In Scotland you can not use them at all, sorry.
Another point with the Berlin space saver stair is that the superb curved treads which give far better access for the feet than other paddle shaped treads actually fall foul of the Regulations because the tread nosing are not parallel. This really is a shame because believe me they are better than anything I have come across in space saver stair treads.
With the use of all space saver stairs I would recommend that you seek advice from your specific Local Authority before you proceed too far. Different Authorities have different opinions on their use.
The space saver stair Doctor