Please can someone tell me whether the pitch of a slate roof is a
building control matter?

We are at the early stages pf planning an extension on a victoriian
house. The roof (slate) currently has a pitch of 16 degeees.
Ideally we like to use 13.5 degrees like the back bedroom has. Both
of these are very shallow.

I want to either extend the roof (by about +50%) or replace it with a
larger one of the same pitch.

I will contract building control to ask them but I thought I'd ask the
opinion here first as people often have useful extra hints on such
matters which can be good to know before contacting BC.

thanks,

Robert

RobertL wrote:
Please can someone tell me whether the pitch of a slate roof is a
building control matter?

We are at the early stages pf planning an extension on a victoriian
house. The roof (slate) currently has a pitch of 16 degeees.
Ideally we like to use 13.5 degrees like the back bedroom has. Both
of these are very shallow.

I want to either extend the roof (by about +50%) or replace it with a
larger one of the same pitch.

I will contract building control to ask them but I thought I'd ask the
opinion here first as people often have useful extra hints on such
matters which can be good to know before contacting BC.

thanks,

Robert
I am not dead sure, but I think it is, from the POV that the roof has to
not leak..

I am not dead sure, but I think it is, from the POV that the roof has
to not leak..

That's what our roofer and also BCO told me in passing . And there was
a thread about this quite recently -
http://groups.google.co.uk/group/uk....f8 01e9d617cf

-
R

"RobertL" wrote in message
...

Please can someone tell me whether the pitch of a slate roof is a
building control matter?

We are at the early stages pf planning an extension on a victoriian
house. The roof (slate) currently has a pitch of 16 degeees.
Ideally we like to use 13.5 degrees like the back bedroom has. Both
of these are very shallow.

I want to either extend the roof (by about +50%) or replace it with a
larger one of the same pitch.

I will contract building control to ask them but I thought I'd ask the
opinion here first as people often have useful extra hints on such
matters which can be good to know before contacting BC.

thanks,

Robert

Yes and the regs are online, google odpm building regs. They're not too bad
to read and at least you can talk with some confidence to the BCO.

On 16 June, 19:01, RobertL wrote:
Please can someone tell me whether the pitch of a slate roof is a
building control matter?

We are at the early stages pf planning an extension on a victoriian
house. *The roof (slate) currently has a pitch of 16 degeees.
Ideally we like to use 13.5 degrees like the back bedroom has. *Both
of these are very shallow.

I want to either extend the roof (by about +50%) or replace it with a
larger one of the same pitch.

I will contract building control to ask them but I thought I'd ask the
opinion here first as people often have useful extra hints on such
matters which can be good to know before contacting BC.

thanks,

Robert

I find these angles surprising - even with heavy Scots slate the
recommended minimum angle to prevent rain being driven under the
slates is around 37 degrees to the horizontal. I'm also surprised at
a Victorian era building having such a shallow pitch as that doesn't
really fit with Victorian design.

There's something that doesn't make sense here as the other factor
with shallow pitch is the wind getting under the slates and lifting
them. The neighbour's new extension with a pitch of 30 to 40 degrees
and Spanish slates is suffering from the slates lifting in a high
wind.
Rob

On Tue, 16 Jun 2009 14:38:09 -0700, Rob G wrote:
I find these angles surprising - even with heavy Scots slate the
recommended minimum angle to prevent rain being driven under the
slates is around 37 degrees to the horizontal.

Maybe we need to multiply by 2.54 to convert imperial to metric

I thought the same - I had a quick google though and saw some companies
quoting 16 degree minimums (couldn't see any at 13.5 though), so it looks
like it's possible even though it doesn't 'feel' right.

cheers

Jules

I find these angles surprising - even with heavy Scots slate the
recommended minimum angle to prevent rain being driven under the
slates is around 37 degrees to the horizontal. I'm also surprised at
a Victorian era building having such a shallow pitch as that doesn't
really fit with Victorian design.

You need to allow for the Victorian terraces with a low* pitched roof to
the "back extension". I live in one and there are very many thousands
more still standing.

*By low here I do not mean 20 degrees.
--
R

Jules wrote:
On Tue, 16 Jun 2009 14:38:09 -0700, Rob G wrote:
I find these angles surprising - even with heavy Scots slate the
recommended minimum angle to prevent rain being driven under the
slates is around 37 degrees to the horizontal.

Maybe we need to multiply by 2.54 to convert imperial to metric

I thought the same - I had a quick google though and saw some companies
quoting 16 degree minimums (couldn't see any at 13.5 though), so it looks
like it's possible even though it doesn't 'feel' right.

cheers

Jules



Wityhout further attention like a flat roof technology underneath, my
architect said

Thatch: 55 degrees
Tiles 40 degrees but builders are thick, and 45 degrees is easy to
calculate.
Slate about 37 degrees, but can be done lower with special care.
Machine tiles that interlock, about 18 degrees..depending on the BCO.

It was the latter that caused teh valley leak that finally made me
decide I was sick of the old house..

On 17 June, 02:59, The Natural Philosopher
wrote:
Jules wrote:
On Tue, 16 Jun 2009 14:38:09 -0700, Rob G wrote:
I find these angles surprising - even with heavy Scots slate the
recommended minimum angle to prevent rain being driven under the
slates *is around 37 degrees to the horizontal.

Maybe we need to multiply by 2.54 to convert imperial to metric

I thought the same - I had a quick google though and saw some companies
quoting 16 degree minimums (couldn't see any at 13.5 though), so it looks
like it's possible even though it doesn't 'feel' right.

cheers

Jules

Wityhout further attention like a flat roof technology underneath, my
architect said

Thatch: 55 degrees
Tiles 40 degrees but builders are thick, and 45 degrees is easy to
calculate.
Slate about 37 degrees, but can be done lower with special care.
Machine tiles that interlock, about 18 degrees..depending on the BCO.

It was the latter that caused teh valley leak that finally made me
decide I was sick of the old house..

I'm using forticrete centurion interlocking concrete tiles, which can
be layed down to 10 degrees on a very simple roof (monopitch, no
valleys etc), 12.5 degrees otherwise. They have various extra
mouldings (OK a ridge and a dent - that's hi tech with tiles !) to
block and divert wind-driven rain, and must all be clipped down.
Simon.

On 17 June, 02:59, The Natural Philosopher
wrote:

Tiles 40 degrees but builders are thick, and 45 degrees is easy to
calculate.

Was it Lutyens who hated 45° pitch and described it as "the evil
angle" ?

On Wed, 17 Jun 2009 02:59:56 +0100, a certain chimpanzee, The Natural
Philosopher randomly hit a keyboard and
produced:

Wityhout further attention like a flat roof technology underneath, my
architect said

Machine tiles that interlock, about 18 degrees..depending on the BCO.

Your architect's a tool, then. The pitch of concrete interlocking
tiles is laid down by the manufacturer. It's not something that is
varied, unless, as you say, you have some additional protection under.
--
Hugo Nebula
"If no one on the Internet wants a piece of this,
just how far from the pack have you strayed?"

Hugo Nebula wrote:
On Wed, 17 Jun 2009 02:59:56 +0100, a certain chimpanzee, The Natural
Philosopher randomly hit a keyboard and
produced:

Wityhout further attention like a flat roof technology underneath, my
architect said

Machine tiles that interlock, about 18 degrees..depending on the BCO.

Your architect's a tool, then. The pitch of concrete interlocking
tiles is laid down by the manufacturer. It's not something that is
varied, unless, as you say, you have some additional protection under.

So you think that if the manufacturers say '17.5 degrees' the roof will
be 100% watertight at 18 degrees and leak like a sieve at 17?

Nothing is exact and precise, and the BCO knows it, and the architect
knows the BCO knows it.

Robert
The pitch of your proposed roof is very much a building control matter, if
your are proposing to use slate the minimum recommended pitch is 22.5. Any
lower pitch them building standards will require details from supplier
confirming the suitability of the roof pitch


Mr T
building standards surveyor

url:http://myreader.co.uk/msg/1391144276.aspx

On 23/04/2010 16:31, david william tainsh wrote:
Robert
The pitch of your proposed roof is very much a building control matter, if
your are proposing to use slate the minimum recommended pitch is 22.5. Any
lower pitch them building standards will require details from supplier
confirming the suitability of the roof pitch


Mr T
building standards surveyor

url:http://myreader.co.uk/msg/1391144276.aspx

You could of course use onduline undersheeting as I did in a previous
house which allows you to use a lower pitch, I had to convince the BC
before starting, but they were quite happy once I'd shown them the
literature.
See : http://www.slecladding.co.uk/ondutile.htm

Don

Donwill wrote:
On 23/04/2010 16:31, david william tainsh wrote:
Robert
The pitch of your proposed roof is very much a building control
matter, if
your are proposing to use slate the minimum recommended pitch is 22.5.
Any
lower pitch them building standards will require details from supplier
confirming the suitability of the roof pitch


Mr T
building standards surveyor

url:http://myreader.co.uk/msg/1391144276.aspx

You could of course use onduline undersheeting as I did in a previous
house which allows you to use a lower pitch, I had to convince the BC
before starting, but they were quite happy once I'd shown them the
literature.
See : http://www.slecladding.co.uk/ondutile.htm

Don

The failure of a low pitched valley was the final nail in the coffin of
my old house.


Leaked like a sieve.

Don't try and be smart with tiled and slated rooves. Or rely on
membranes underneath

Get the pitch right.