Loft Conversion

[Chris]

Hi Summer is close, got a few weeks off work, I challenge myself to get the loft converted at last. I am going to go for a DIY install, now I passed through a friends house the other day and he has got a pro in to do it, but I noticed when I took a quick look up the hatch that the floor had been raised with planks of wood. I did not have time to see how / in what direction they were in comparison to the joists etc, I assume that the builder strengthened the floor. I would like to strengthen the floor in my loft, but I was just wondering how and what would be the best way to do it. I want the floor to be strong enough to hold a person so it could be used as a room if need be for TV + Sofa etc for the kids.

Also are there any online guide's available on the internet on how to convert a loft etc, just for some guidance.

Thanks Allot Chris

[Hugo Nebula]

On Sat, 12 Jun 2004 15:43:15 +0100, a particular chimpanzee named "Chris" randomly hit the keyboard and produced:

't enable you to design a conversion, but it should be able to give you an indication of what you need to look for. If you're unsure of the basics, like the depth of floor joists required, then I would suggest that you have plans drawn up by a surveyor or architect, with the structural alterations designed by a structural engineer.

[Terry]

"Hugo Nebula" wrote in message news: [e-mail]...

Well there are tables of how long a span floor joist can be, using various thicknesses, types, quality and depths of wood. And one can 'double up' ceiling joists to become floor joists using fairly common building carpentry practices. But respectfully suggest that if you have no building experience/feel for what would be correct you get some advice, otherwise you could cause 'saggy' ceilings, problems rerouting existing ceiling wiring, allowing for plumbing vents through to the roof etc. Also even though your handwork might be fine and completely usable, your insurance company might not like that or might deem that non standard construction is not insurable? Also in many jurisdictions lofts are not permissible as 'living space' or at least not without exits and smoke alarms etc. for safety; therefore loft space only usable for storage which is accessed occasionally! Whether allowing the children to play up there during the day, while adults present downstairs, would be allowable is probably moot? But without a window/s accessible from the ground, for a rescue or fireman's hose ladder, using attic/loft for 'living' activities not a good idea at all IMHO. Since attics are supposed to be ventilated you may have to install a vapour barrier on the inside (warm) side of any finished walls you install up there otherwise warm damp house air may condense in unventilated spaces and cause damp, mould and rot. Mould bad for health and rot bad for roof.! Not trying to be negative but be careful. We've had posts on this ng, from time to time, that indicate in some instances, very little awareness of the use of vapour barriers, insulation of outer walls etc. There was one case, either on this or a similar discussion forum, where someone had mould (fungus?) growing on inside of their, presumably rapidly rotting, wood roof rafters! I presume they were NOT joking.

[pjdesign]

Hi Chris. Take a look at this.

good place to start.

Baz

[Christian McArdle]

The loft conversion will be subject to building control (and in some cases planning permission). The building control officer will need to have structural details of how you propose to strengthen the floor. You will probably also need structural alterations to the roof to remove struts which will need careful design and calculation. There are a number of other things that will need to be sorted too. Here's a list off the top of my head, there's probably more.

1. Mains powered linked smoke detectors on every floor.
2. Protected main stairway to the outside (there are several options).
3. Escape window reachable by ladder low down so a children could be carried through.
4. High levels of insulation to the rafters with either 5cm ventilation behind the insulation, or breathable membrane (which requires reroofing, but gives more headroom). This will typically require around 40mm from the rafter, although this is variable.
5. Joists strengthening. This will typically raise the floor by around

100mm.

1. Approved staircase.
2. Firedoor at top or bottom of stairs.
3. Roof redesign to remove struts or insert Velux windows.

Christian.

[Bob Mannix]

All of what Christian says is true but you should add:

1. 30 minute fire protection between loft conversion and rest of house (the firedoor is part of this).

and to add to 3: the window must be reachable by ladder from the road side of the house (ie if there is no direct access to the rear of the property the window must be at the front).

You may also need planning permission but that depends on what you overlook and what you intend to do and may not be necessary for you.

If you think all this a bit OTT, wait until your kids have a friends to sleep over and they are in the loft. At that point you become quite glad you did things "by the book". That's aside from any problems you may have selling without a building regs certificate, which you may not regard as important. This is all for a "habitable" room. Normally this is defined by the presence of a staircase. If the access is solely by a drop down ladder, you can generally claim that it is not a "habitable room" but, if you are going to use it as if it was, you may, on reflection, decide that a "proper job" is better.

Generally speaking, while theoretically within the scope of a good d-i-yer, the structural part of a loft conversion is more normally done by a specialist contractor. The fitting out (wiring, flooring, insulation, plasterboarding/plastering, smoke alarms etc) can then be done by the d-i-yer to save costs.