RHS Limited
226-228 Holbrook Lane
If you already have a stair down to an existing cellar, the chances are that the property is at least 100 years old and the staircase will almost certainly not comply with current regulations. This is not a problem, but if what you are talking about is upgrading the cellar and changing the staircase, then the Building Regulations apply, as they do for any structural alterations.
It may be impossible to fit a regulation compliant staircase into the space that you have for access to your cellar, but you really need to seek advise from your Local Authority Building Control department as to what they will allow you to do.
I accept that a lot of people will cringe at the thought of going to the Local Authority for advice, but in my own experience I have found them more help than hindrance, particularly these days when they are competing for business with independent private inspection services. I also think that means of access to converted cellars need some careful thought irrespective of the regulations. In the event of a house fire a cellar is probably the worst place in your house to escape from. I know it may never happen, but it is worth preparing for with as good an escape staircase as you can muster.
The Staircase Doctor
The Architect on this project had produced as drawing showing a 1500mm diameter spiral staircase with a centre tread going of 220mm.that is to serve as access to a one bedroom loft conversion.
Now I know why she had done that, but I also know why the questioner is having problems getting the spiral staircase actually made.
Part K of the Building Regulations (England and Wales) calls for a minimum centre going on a staircase to be 220mm. This allows enough tread depth for your average size 14 shoe sized teenager to stagger drunkenly up the stairs to their crash pad. However on spiral stairs it is a different ball game under different rules. It is difficult to explain why in a few words but basically a 220mm going on a smaller diameter spiral staircase would produce a stair where the treads above your head would be too low, and would reduce the head clearance height to less than the required 2000mm. So spiral staircase designers resort to using BS 5395 part 2 which covers spiral stairs and has a set of rules that work. This approach is acceptable under the Building Regulations as an alternative approach.
You can tell how far out Part K of the Regulations are when applied to spiral staircases when you compare the 220mm. centre going of the Regulations with the 145mm centre going requirement of the BS. As you can see there is a world of difference but the BS works and is tried and tested.
So your Architect is right but wrong and you would be doing her a favour to point this out. As for your project go with a stair that can meet the BS and tell the Inspector what you are doing and why, you should not have any further problems.
The Spiral Staircase Doctor.
Typical concertina type electric loft ladders weigh around 60 kgs. all in, that is including the hatch and frame etc. This should not normally require any special treatment. Original Loft floor joists are not normally sized to take regular foot traffic so will probably need beefing up in any case if you intend getting more use out of the loft. I assume that this is the case as you are thinking about spending on an electric loft ladder. I do not have enough details and it is beyond the scope of this blog in any case to give specific structural recommendations for your particular loft, but any reputable loft contractor ought to be able to advise you on what is needed.
I think it is worth advising whoever is going to carry out the work in your loft that you intend adding an electric loft ladder that has a self weight approx 60 kgs. The chances are that your existing loft hatch will in any case need enlarging to receive an electric loft ladder which typically will require an opening of 700mm x 1000mm. While making the opening bigger they will probably need to cut through existing joist members and that is is the time to consider what structural elements are need to safely trim the new opening. Trimming an opening to form a floor aperture is not rocket science for your average carpenter and I doubt that a 60kg electric loft ladder will pose any serious problems, but do make sure that they are aware of what you are installing.
Not connected to weight but also worth remembering at an early stage in the works is that an electric loft ladder requires the vital ingredient of electricity in order to work. Before everything gets covered up make sure you have a nice switched supply within the vicinity of the hatch aperture
The Electric loft ladder Doctor
This question in full explained that the balustrade and treads to this large old cast spiral staircase had big gaps in it that children could climb through. They also now had a need to extend the spiral stair upwards to new loft bedroom. The following is the Staircase Doctors reply.
You have raised some good questions, unfortunately the answers are not so easy to explain but here goes
You could possibly infill the gaps in the existing spiral stair but there is not likely to be a matching product, and you would be unlikely to get any other stair manufacturer (other than perhaps the one that made the stair) to show an interest in it.
Putting one spiral on top of another existing one is possible but it is not really practical (and may be impossible) to use another manufacturers product.
A better solution would be to replace the lot in one go with a new double height spiral. However these can sometimes have layout problems which make it difficult to do for your specific stepping on and off point requirements. The reason for this is that the rotation of a spiral stair is really a fixed number of degrees per tread depending on the diameter. So depending on the number of treads in total this will determine the total rotation of the whole flight. This means that if you have to start at a particular access point at the bottom, the landing at the top may not be where you want it to be to suit your floor layout.The problem gets worse with double height spirals because you have an extra landing halfway up as well as one at the top.None of this may be a problem in your case, but I really need more details of your floor layouts and storey heights in order to advise.
Another point worth noting at this stage is that The British Standards covering spiral staircases requires a main house spiral stair serving the bedrooms on your first floor to be about 2000mm in diameter, and the secondary stair serving a one bedroom loft conversion to be about 1500mm in diameter. So it is worth checking to see that you have enough floor space in your proposed loft conversion to accommodate an approx 1500mm diameter hole in the floor
The Staircase Doctor
Oh dear my heart always sinks when the first question people ask about an important product like a spiral staircase is about the colour. Sure I know it is important but too much emphasis on matching wood shades nearly always ends in disappointment. Wood is a natural product and you will get variation in colour within the same tree never mind different trees from different countries. Add to this the fact that most solid wood spiral staircases are manufactured of Lamila, a product that glues together finger sized blocks of wood to make up a solid plank. This helps prevent warping and is greener because it reduces wastage, but it means that you can have several different colour and grain types in the same tread of a spiral stair. There is also another problem that I have personal experience of, that is mellowing. All natural wood will change colour with age and with exposure to things like sunlight. A few years ago under great pressure from 'her who has to be obeyed' I installed a white American solid oak floor throughout Staircase Castle. I have never been convinced that there is actually a white oak tree but it was a light bleached colour and looked very nice. Now a few years later it is a sort of deep yellow and nothing like the original colour, but hey that is the beauty of a natural product and I love it. Ask anyone on the Antiques Road Show and they will tell you that the value increases with that beautiful natural patina that only arrives with age.
So to answer the enquirers question more directly. You will not get a modular kit spiral staircase in a white oak, but you can get someone to make one for you. However be aware that they can only work with the timber that they are supplied, there is likely to be a variation in shade from any sample that they might show you prior to order. From the day that you install the spiral staircase it will start to slowly change in colour and will probably not be an exact match for your kitchen units in the first place. So expect this, do not worry about it, and you will live longer.
The Staircase Doctor