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May 08, 2012

Can I get an electric loft ladder hatch size of 1000 x 2000mm.

There are manufacturers of timber electrically opening loft ladders that might consider attempting such a large hatch size but it would very expensive and the sheer weight involved in opening and closing the hatch would require some very serious and expensive operating system.

Standard metal concertina style electric loft ladders tend to have a sensible maximum opening size of 1200mm x 700mm. I say sensible because this is about the maximum that an off the shelf operating system would manage on a regular basis without problems. Personally if I needed such a large opening that you are considering, I would probably look to another solution like a nonelectric model with some serious counterbalancing springs to make it more comfortable to operate.

I would also consider using a standard sized metal electric concertina system for regular access, then if possible add another bigger manual trap door(no ladder) adjacent to it for the odd occasions when you need to get a grand piano up to the loft floor.

I am always hesitant about recommending anything that goes to extreme of what is a practical possibility. I always feel that any cutting edge technology is better bought into after the inevitable initial design faults have been corrected, or at least the product has been proven to work. I feel that getting involved in very large electric loft ladder sizes would be a step into the unknown, and I would prefer not to be a guinea pig.

The electric loft ladder Doctor

May 04, 2012

A what step can you walk under a typical kit spiral stair.

This is really a "how long is a piece of string" question, the answer being that it all depends on the spiral stair construction and the spiral stair height.

I can however tell how you work this out for any spiral staircase.

First you need plan drawing showing the rotation of the treads for your specific spiral. With standard spiral stair kit like the Klan or Genius these are r available on the web, or ask your supplier who should be able to supply one. This will show you the relative positions of the treads, which will allow you to roughly plot on the floor where each tread will be on your specific project.

Then you need to measure the floor-to-floor height that your spiral stair needs to achieve. Armed with this dimension you divide it by the number of treads that you intend using. With kit stairs like the Klan spiral staircase you want to achieve a individual tread rise between 210mm (the minimum kit tread rise) and 220mm (the maximum allowed under UK Building Regulations). For example, lets say a floor-to-floor height of 2743mm divided by 13 treads gives an individual tread rise of 211mm, which is fine.

Now you can calculate the height of any tread on your proposed spiral staircase. For example tread 10 would be 211mm x 10 high = 2110mm. This is to the top of the tread, so for head clearance height under the tread you would need to deduct the tread thickness and any support element that projects below the spiral stair tread. In the case of say the Klan or Genius range of spirals, and in fact most other kit spiral stairs on the market, the tread thickness is between 40 and 45mm. Therefore your height under tread 10 will be about 2065mm.

The height under tread 9 will be 2065 minus the tread rise of 211mm = 1854mm. Therefore from these calculations you can see that tread 10 gives a nice at least 2000mm head clearance height, where as tread nine is too low for the big guys in your household.

So now you can can calculate your head clearance height for any spiral staircase using this method. Bear in mind that with a spiral stair, each tread is overlapped and under lapped by the treads above and below it. As rule of thumb if you think you need walk under tread 10 it is always safer to base your calculations on tread 9 below it to be on the safe side.

The spiral staircase Doctor.

April 18, 2012

Do Electric Loft Ladders Require Annual Maintenance

Most manufacturers include details of any maintenance on their electric loft ladders together with any warnings about misuse. In most cases these documents are really produced (in my opinion) more to cover them with an "I warned you about that" clause rather than to be any help to the user. The truth is there is really very little maintenance that is possible or required other than the obvious looking to see if anything has broken.

The moving parts of most concertina style electric loft ladders are usually aluminium castings with steel inserts, they move relatively slowly and not very often compared to say a car engine. I have never seen anyone recommend lubrication to these parts and I think there is a good reason for this. A. it is not necessary and B. it can do more harm than good, as grease or oil attracts dust that will eventually cause the joint to freeze rather than help it move.

All mechanical devices by the nature of the beast will wear out and will require replacement parts at some point. In the case of an electric loft ladder there is very little that you can do to extend the natural life of any element of the device. However the good news is that unless you are using your loft ladder all day every day you should get more than your monies worth out of it.

The most likely things to wear out are the electric motor or the drive elements, which are usually a rack and pinion type drive rather than a hydraulic ram. Like a lot of modern devices these tend to be sealed for life units needing no maintenance.

You could probably get a failed motor rewound or repaired but in this day and age it is likely to be more economical to replace rather than repair. The fact is that both the motor and the drive mechanism are usually supplied as one complete unit that is used to move entrance gates as well as electric loft ladders.

They are not that cheap to replace but having had probably 15 years of experience with electric loft ladders I can honestly say that I have only recently supplied my first replacement. Bearing that in mind I think that there is very little chance that you will have to replace your mechanism.

The electric loft ladder Doctor

April 16, 2012

Can a Karina space saver stair make a turn through ninety degrees at the top.

Karina space saver staircases can turn through ninety degrees at the top, unfortunately you will struggle to find this layout in any brochure or anything that you can find on the web. I have never understood why this is, because it is a useful layout in many situations, especially where the access point happens to be very close to a wall.

To make a right angled turn at the top of a Karina spaces saver stair you will turn the top 5 treads 18 degrees each to make a total of 90 degrees. This will produce a footprint (area taken up by stair on the floor) for a 12 riser stair of 1500mm x 770mm. This layout will require a finished size aperture in the upper floor of approx 1400mm x 850mm

One point to be aware of when the turn at the top is made into the corner of two walls of the downstairs room, you will create an area on the outside of the curve where people can get trapped if they fall between the walls and the space saver stair. It is actually possible to put a handrail on this side using the standard balustrade supplied with the kit. In a standard Karina space saver stair kit you are supplied with 15 hockey stick style balusters. You will use 8 of these to put a complete handrail on the inside of the curve, and the remaining 7 will create a balustrade on the outside of the curve from treads 7 to 11, which covers the area of danger in the wall corner.

The space saver stairs Doctor

April 10, 2012

What are the installation costs for space saver stairs from landing to loft.

It is always very difficult to give an idea of installation costs for space saver stairs projects. The costs vary considerably around the country, and the work involved can also vary considerably between projects.

The best I can offer is to say that typical kit space saver stairs such as the Karina, Kya, Gamia Mini or Berlin can take a tradesman (plus probably an extra pair of hands) or skilled DIY installer about a days labour to erect. So you can have a stab at the costs involved for that element of the installation. However bear in mind that a self employed builder or small building company have considerable overheads over and above a days wages, so be sensible about what you are likely to pay.

The more difficult cost element to predict for the installation of space saver staircases is the formation of the aperture in the upper floor. This requires structural alteration of the supporting joists, then making good to the plastered ceiling and floor boarding.

How difficult this turns out to be, all depends on the specific details and construction. Also do not be fooled into thinking that because you already have a loft ladder hatch in place that this will will be adequate for your space saver stair. Invariably your existing hatch will need to be enlarged to accommodate a typical space saver stair.

Again having a guess at man hours for the formation of a new aperture on a typical project I would say at one day for a tradesman.

Obviously the only real way to find is to ask, personally I would be aiming at a local one man band or small local company preferably carpentry based. Although I have to say that in my experience common sense and the patience to read instructions and act accordingly can prove to be just as successful as the type of time served tradesman or worse still an engineer who assume that they know everything and therefore do not need to read instructions!

The Space Saver Stairs Doctor.

March 21, 2012

If a loft is used for storage only, does the loft staircase need to comply with the Regulations.

People often tell me that if a room is non habitable then it does not need to comply with the Building Regulations. I do not agree with that statement, particularly when they are talking about a staircase serving a room in their house such as a loft room. A new staircase inside a house is a structural alteration irrespective of what sort of room it serves. It is also has the potential to present a risk to the health of its users. It should therefore be constructed to comply with the current Building Regulations.

You could argue that as loft storage area it will not have as much regular use as say a bedroom, therefore it presents less potential risk. That is true, but the fact that you are actually installing a loft staircase to an area that is normally served by a loft ladder, implies the likelihood of more regular use. There is also the fact that once a staircase has been installed, you or future occupiers could at any time start to use that area as habitable room.

I fully understand that all you are trying to do is put a better access to your loft storage area via a loft staircase, but I do not think that your Local Authority Building Control Department would view it that way. It is however worth asking them, you never know they may have have a different opinion.

The staircase Doctor.

March 19, 2012

Can a spiral stair to my wine cellar finish at ground floor level with a hatch door.

Yes it can, I have been involved in several projects that have had spiral stairs to cellars exiting to the ground floor via a hatch door. There are however things that need to be considered.

First you have to bear in mind that the balustrade of a spiral staircase and in fact any staircase does not finish at the upper floor level but stands up above the floor by at least 900mm.This allows you to grab the handrail before you actually take a step down the spiral stair. By having a closable hatch at floor level the spiral staircase hand railing needs to adapted so that it also ends at floor level.

This is possible but it does mean that you will have nothing to hold onto for the top three or four steps of the spiral stair. This will be most obvious when you are descending because it requires you to step down onto the stair into the abyss without the secure feeling of holding onto something.

A solution to this, although it is not always possible, is to have a handrail fastened to the underside of the hatch door. This works well providing that have a hatch door that opens to the vertical position and is along side the first step of the spiral staircase.

This leads to to the second thing to consider, which is the hatch itself. All staircases require stairwell apertures to be large enough to give you enough head clearance height under the ceiling as you descend or ascend the stair. This is invariably larger than you might expect, in the case of spiral staircases for instance it will typically need be about the same area as the spiral stair itself. So a 1200mm diameter spiral will need a hatch door or doors of about 1200 x 1200mm.

This is a large hatch and serious consideration has to be given to how it will work and how heavy it is to lift. That said I have seen workable solutions, but these usually end up requiring more design and larger expenditure that most people at first envisage.

As I have already said I have seen spiral staircases and flight stairs successfully ending at cellar hatch doors, but do not under estimate the problem, and remember that the hatch door has to capable to take foot traffic when closed, so strength as well as weight and size need to be carefully considered.

The Spiral Staircase Doctor

March 14, 2012

My London flat has a ladder access to the bedroom, can I replace it with a loft stair .

It is amazing how many times I have been asked this question recently. I suppose it is a sign of the times, with London developers creating bijou flats out of what in the rest of the country would be called a broom cupboard. Nice business if the demand is bigger than the supply, which it appears to be in London even in a recession.

I suppose the first question you have to ask yourself is, if a loft stair is possible why did the developer use a ladder. The answer could be cost, but most of the broom cupboard conversions that I have seen in the metropolis have been done to a high specification. So I do not think that the cost of a kit space saver loft stair would break the bank. The more likely reason is that a ladder saves a little space over a space saver loft staircase, and space is a big selling point in live in cupboards. I am talking about space saver loft stairs as opposed to a full staircases under the assumption that you do not have the room for a full staircase.

So you buy your bijou apartment because of the location near a tube station, and because you like the colour scheme, but then you discover that ladders are not the best thing to access calls of nature in the middle of the night. The solution a nice space saver loft stair purchased off the web.

Up to now I do not think our questioner has put a foot wrong, particularly asking if it will work before going any further. In my opinion A space saver loft stair kit will provide a much more usable means of access than any ladder, providing that you have a large enough aperture in the upper floor to accommodate it, and enough space downstairs for the footprint.

Typically for space saver loft stairs such as the Karina, Kya or Gamia Mini this will mean a 1400mm x 700mm aperture for a straight stair or 1400 x 900mm for a stair that turns through 90 degrees. The footprint, which is the length and breadth of the stair on plan will be 1550mm x 700mm for a straight stair and 1550mm x 900mm for a stair that turns. These dimensions are only approximate, and are for a standard 12 riser space saver staircase, a higher or lower stair will use more or less space.

As always get someone in the know to check you specific layout to see if it will work before you buy.

The loft stair in a broom cupboard Doctor.

March 12, 2012

Can a loft stair be steeper and narrower than a normal stair.

By a loft stair I think you are referring to a staircase that serves a loft conversion in your house. If so the answer is yes but there are restrictions

In England and Wales the Building Regulations allow for the use of alternate tread space saver stairs to serve a one room loft conversion. So you can use this type of loft stair, which is steeper, and usually narrower than a normal house staircase providing that.

  • It only serves one room not two or more.
  • The loft room is not a kitchen or a lounge, however it can have an attached bathroom providing it is not the only bathroom in the property.
  • There is no room to install a standard full staircase.
  • There is a handrail on both sides
  • The tread nosings are parallel
  • It complies with all other requirements of part K of the Regulations

Please note that this type of loft staircase is not allowed under Scottish regulations. Also bear in mind that a steeper narrower stair is by nature not as comfortable to use as a standard stair. That said if space is at a premium it will allow you to gain far better access to the loft when compared to say a loft ladder.

the Loft Stair Doctor

March 10, 2012

Can you have an extra landing half way up a spiral stair.

Yes it is possible to put a landing tread in the middle of a spiral staircase. In fact for very high spiral stairs it is desirable to have say double sized tread about halfway up to give less able users a resting station. Technically the only problems are designing it so that you do not impinge on the head height clearance on the treads beneath the extra landing, and designing the helical handrail so that it has a horizontal bit in the middle to suit the extra landing.

These two requirements do tend to take it out of the realm of the modular kit spirals and into the more expensive bespoke spiral stairs. However there is no reason why a modular kit spiral cannot be supplied with two landing treads as long as you are prepared to adapt the handrail elements to cater with the horizontal section in the middle. You are however likely to be on your own when comes to instructions of how to do this. I know of no manufacturer who has gone to the trouble of producing instructions for such a rare requirement as this.

Normally when people ask me this question they are not thinking about a rest station half way up the spiral staircase, but are usually thinking of actually stepping off at that point to access a bed loft or a library balcony etc. Again there there is no technical reason why you cannot do this. However the more likely thing to make it a non-starter, is that unless you are very lucky, the fixed tread rotation of a spiral stair is likely to mean that the mid height landing is not pointing in the direction that you require.

As always talk to a man who knows about your specific requirements, before you go too far with your plans.

The spiral staircase Doctor