Floor type for extension
PaulB
house has a suspended wooden floorboard ground floor, and I'm
wondering what to do for the extension?
I'm assuming we're allowed under BR to have a suspended wooden floor
for the extension too? However, it seems most houses/extensions are
built with a solid concrete/screed floor now - I guess this is more
energy efficient (and less squeaky!) - so my questions are:
1) Am I right to assume we could do a suspended wooden floor in the
extension if we wanted to?
2) Is there likely to be a big difference in cost (it's around 30m2 at
ground floor level) between the two methods of construction?
3) If we went for a solid ground floor, what do we do with the below-
floor air vents from the existing house which abut the extension?
4) Are there any other good reasons to choose one method over the
other?
TIA for advice.
Paul.
sm_jamieson
> We're planning a side extension for our 1970's house. The existing
> house has a suspended wooden floorboard ground floor, and I'm
> wondering what to do for the extension?
>
> I'm assuming we're allowed under BR to have a suspended wooden floor
> for the extension too? However, it seems most houses/extensions are
> built with a solid concrete/screed floor now - I guess this is more
> energy efficient (and less squeaky!) - so my questions are:
> 1) Am I right to assume we could do a suspended wooden floor in the
> extension if we wanted to?
> 2) Is there likely to be a big difference in cost (it's around 30m2 at
> ground floor level) between the two methods of construction?
Not sure, but more weight bearing on the foundations, so could
possibly affect them.
> 3) If we went for a solid ground floor, what do we do with the below-
> floor air vents from the existing house which abut the extension?
I've just done this. The vents must be carried under the new floor
slab. Usual method is to use underground drainage componenets (brown
110mm pipe), and offset cavity wall vents to connect the piping below
the slab up through the cavity to an airbrick above the DPC. There is
an adapter to connect the piping to the cavity vent. I got mine from
buildbase (manufacturer timloc I think).
See near the bottom of this page (this is an excellent site by the way
- [nothing to do with me]). The parts look identical to the bits I
used :-
http://www.myhouseextension.com/slab3.htm
> 4) Are there any other good reasons to choose one method over the
> other?
Less squeaky floor.
Room usage might be a factor. e.g. kitchen as usually solid floor
(originally so they could be hosed down !), but a washing machine on a
suspended floor makes an awful racket.
>
> TIA for advice.
>
> Paul.
Tournifreak
>
> > 4) Are there any other good reasons to choose one method over the
> > other?
More choice of floor coverings with a concrete floor. (eg tiles)
Underfloor heating then also becomes a sensible option.
Jon.
Hugo Nebula
PaulB <paulm...@googlemail.com> randomly hit the keyboard and
produced:
>We're planning a side extension for our 1970's house. The existing
>house has a suspended wooden floorboard ground floor, and I'm
>wondering what to do for the extension?
>
>I'm assuming we're allowed under BR to have a suspended wooden floor
>for the extension too? However, it seems most houses/extensions are
>built with a solid concrete/screed floor now - I guess this is more
>energy efficient (and less squeaky!) - so my questions are:
>1) Am I right to assume we could do a suspended wooden floor in the
>extension if we wanted to?
It depends on how far above ground level your floor will be. You need
to provide a minimum of 150mm clear airgap between the bottom of your
joists and the top of the concrete oversite. This oversite must be no
lower than the adjoining ground on at least one side of the building.
Therefore the finished floor level must be at least (25mm floorboards
+ 100mm joists + 150mm airgap) 275mm-300mm above the ground.
If you haven't got this height, then timber floors are not practical.
That's not to say they can't be installed, but you're then looking at
something akin to a basement. Another option is to have a concrete
slab but lay floorboards on battens over.
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"
Andrew Gabriel
Hugo Nebula <abuse@localhost> writes:
> It depends on how far above ground level your floor will be. You need
> to provide a minimum of 150mm clear airgap between the bottom of your
> joists and the top of the concrete oversite. This oversite must be no
> lower than the adjoining ground on at least one side of the building.
> Therefore the finished floor level must be at least (25mm floorboards
> + 100mm joists + 150mm airgap) 275mm-300mm above the ground.
>
> If you haven't got this height, then timber floors are not practical.
> That's not to say they can't be installed, but you're then looking at
> something akin to a basement. Another option is to have a concrete
> slab but lay floorboards on battens over.
Two houses were built near me about 5 years ago.
At one point, I looked in and they had the ground floor
joists there, except they were concrete lintels ("T"
profile IIRC). Next time I looked in, there was a screeded
floor there - I didn't see what went between that and the
lintels. There are air bricks around the houses under the
floor level, so I presume there's an air space under the
floor. Wouldn't be very easy cutting a trap door to gain
access to it though.
--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
dennis@home
"Andrew Gabriel" <and...@cucumber.demon.co.uk> wrote in message
news:487295b0$0$78075$5a6a...@news.aaisp.net.uk...
http://www.hanson.co.uk/45/floorsandprecast/beamandblockfloors.html
Andrew Gabriel
That looks like it!
Looks very unfriendly for any later DIY work though.
sm_jamieson
> In article <kpu474t251ee8h3nqc9ujca3km1smko...@4ax.com>,
screeded over.
Simon.