Low pitch loft conversion

[BobSaunders]

We have an L shaped house, and the height between ridge and the top of the joist is 2.2metres.

Anyone here done it without dormers? A velux conversion? Thinking office and a guest bedroom with ensuite.

[sfella]

To meet building regs you need to achieve 2.1m at the top of the stairs. You will need to accommodate some insulation across the underside of the roof timbers plus plasterboard and that's all assuming the current timbers both roof and floor are big enough.

I'm sure someone more versed in loft conversions will be long but anytime someone has spoken to me about them they've turned into more of a pain than what they have been worth.

Last time we needed to go upwards on a dormer bungalow we took the roof off,built up to conventional two storey and then dropped attic trusses on to get the 3rd storey.

[Little Lofty]

Ideally you need around 2.4m to start off with, you’ll lose around 300-400mm insulating the roof and constructing a new floor. You need 2.0m minimum at the top of the new stairs, you can sometimes get away with 1.9m but even 2.0m is a bit low for comfort. Lowering the ceilings is sometimes an option but a bit messy.

[Murph7355]

To be a pedant, I think the 2m is meant to be above the entire pitch line.

Ours is *just* on this...at 6'4" (so 1.93m) it feels marginal coming downstairs.

Bear in mind also that with the ridge to joist height you've noted, you're not going to have a massive amount of usable space up there into the eaves.

[Aluminati]

As has been said, 2.2 to underside of ridge is a pretty useless space. Last one I did I changed the pitch on for this reason.

[BobSaunders]

Yeah, I think I’m pretty much stuffed on this one.

[Little Lofty]

Murph7355 said:

To be a pedant, I think the 2m is meant to be above the entire pitch line.

Ours is *just* on this...at 6'4" (so 1.93m) it feels marginal coming downstairs.

Bear in mind also that with the ridge to joist height you've noted, you're not going to have a massive amount of usable space up there into the eaves.

Yes you do need 2m on the pitch line but most BCO’s are quite flexible if it varies slightly.
I’ve fitted a Velux and at the top to gain a few mm, there is no minimum in the rooms (bizarrely) but you generally need 2m for the fire doors if they can’t go at the bottom of the staircase. 2.2m existing height would need the ceilings dropped or roof raised.

[Equus]

Little Lofty said:

Yes you do need 2m on the pitch line but most BCO’s are quite flexible if it varies slightly.

There's an 'official' relaxation down to 1.9m. on the centreline of the stair/1.8m at eaves, for loft conversions.

See diagram 1.4 on page 8 or THIS document.

[Little Lofty]

Equus said:

There's an 'official' relaxation down to 1.9m. on the centreline of the stair/1.8m at eaves, for loft conversions.

See diagram 1.4 on page 8 or THIS document.

I’ve always found most BCO’s quite flexible on loft conversions, e,g if the existing staircase only has 1.8m they will allow the same on the new stairs etc, landing sizes are pretty flexible too, if everything had to be done by the book many lofts just wouldn't work.

[Welshbeef]

Aluminati said:

As has been said, 2.2 to underside of ridge is a pretty useless space. Last one I did I changed the pitch on for this reason.

Did that enhanced roof height need full planning permission?

[paulrockliffe]

What's the layout and options for the stairs? If you can make the stairs work then it's really your call as to how useful the rest of the room is with whatever height is left. For an office and bedroom where you're mostly sat down or asleep it works better. For kids it works even better again.

We had a typical Victorian rear 'extension' (I put that in inverted commas as unlike most of them round here it was built with the house), we took that up to three stories with an end gable at pretty much the main ridge height, which then let us put the stairs right under the main roof eaves and comfortably get the head room over the stairs.

[Equus]

Little Lofty said:

I’ve always found most BCO’s quite flexible on loft conversions, e,g if the existing staircase only has 1.8m they will allow the same on the new stairs etc, landing sizes are pretty flexible too, if everything had to be done by the book many lofts just wouldn't work.

I've known both: some will be flexible, and yes they'll usually let you match existing, if existing is lower; others will tell you that the Regs have already allowed the flexibility, and they have to draw the line somewhere (which is fair enough, I guess... lower than 1.9m. is really very low).

I'm sure that most BCO's would tell you (quite rightly) that it's not their job to allow something that doesn't work, just because there's no practical alternative: if it doesn't work, it doesn't work.

[BobSaunders]

paulrockliffe said:

What's the layout and options for the stairs? If you can make the stairs work then it's really your call as to how useful the rest of the room is with whatever height is left. For an office and bedroom where you're mostly sat down or asleep it works better. For kids it works even better again.

We had a typical Victorian rear 'extension' (I put that in inverted commas as unlike most of them round here it was built with the house), we took that up to three stories with an end gable at pretty much the main ridge height, which then let us put the stairs right under the main roof eaves and comfortably get the head room over the stairs.

We can comfortably get the stairs in so that it ends up under the roof truss. As you say, it's trying to work out if what is left up there height wise is usable.

The long part of the L is comfortably over 12 metres in length, but only 5 metres wide, similary the small part of the L is 5.0 metres by 5metres (where we would exit the stairs, So reality is we are playing with not a lot - which lent my thought process to a small office and a small guest bedroom with ensuite.

[BobSaunders]

Hey Equus -

I've seen some companies advertising turn rooms into usable hobby rooms which are not classed as usable bedrooms. Is this just skirting planning laws? - https://loft-boarding-nw.co.uk/miniloft

[Welshbeef]

BobSaunders said:

Hey Equus -

I've seen some companies advertising turn rooms into usable hobby rooms which are not classed as usable bedrooms. Is this just skirting planning laws? - https://loft-boarding-nw.co.uk/miniloft

Even though permitted permission is enough I’d always go for the full planning permission and building regs.

Makes it 100% a non issue come selling

[Little Lofty]

Lofts rarely need planning permission but ALWAYS need building regs. There is no such thing as an office/playroom, if it looks like a room it is a room and needs building regs.

[Equus]

BobSaunders said:

I've seen some companies advertising turn rooms into usable hobby rooms which are not classed as usable bedrooms. Is this just skirting planning laws?

It may be an attempt to dodge Building Regulations (Planning doesn't care): but it's very dodgy... the LABC (the national coordinating body for Local Authority Building Control) has published clear guidelines about what is considered to be a habitable room and calling it a 'hobby' room does not cut the mustard!

Bottom line is that if it's obviously set up for more than basic storage with occasional access, its habitable.

[Little Lofty]

When I done lofts there was a local guy doing unofficial lofts for £6/7k. The LABC we’re trying to get him to stop, there are still loads getting done though. There’s a guy on YouTube who does loads and seems to get away with it.