Following on from the Solar PV panel thread (very useful info, thanks to
all contributors), I don't have a south-facing roof. However, I have a
flat garage (felted) roof which would be well positioned. Is it possible:

(a) that there are solar panels that come with stands so can sit on a
flat roof

(b) that the roof be strong enough to hold solar panels (or would it
have to be reinforced which would probably blow the economics out of the
water) (the roof is strong enough to walk across carefully for
occasional inspection purposes; 1980s build)

TIA
Allan

Allan wrote:
Following on from the Solar PV panel thread (very useful info, thanks to
all contributors), I don't have a south-facing roof. However, I have a
flat garage (felted) roof which would be well positioned. Is it possible:

(a) that there are solar panels that come with stands so can sit on a
flat roof

Yes.

(b) that the roof be strong enough to hold solar panels (or would it
have to be reinforced which would probably blow the economics out of the
water) (the roof is strong enough to walk across carefully for
occasional inspection purposes; 1980s build)

You'll need to either provide the sizes and spacing and condition of
rafters, condition and construction details such as the type of covering
(Plywood, planks, thickness and number of layers of felt....) and the
span, or (preferably and strongly recommended) get a proper structural
survey done, which will require clear access to the underside of the
roof, with no ceiling in the way, but will only take a few minutes with
clear access.

The answer is a definite maybe, depending on what panels you use, and
the roof design and condition. It may be, at 20 - 30 years of age, your
roof is due for replacement anyway, depending on the maintenance that
has been carried out.

--
Tciao for Now!

John.

Allan wrote:

Following on from the Solar PV panel thread (very useful info, thanks to
all contributors), I don't have a south-facing roof. However, I have a
flat garage (felted) roof which would be well positioned. Is it possible:

(a) that there are solar panels that come with stands so can sit on a
flat roof

Yes, the installers will have suitable kit to do this. It would
probably be outside the limits of planning "permitted
development"(1), which would mean putting in an application.

(b) that the roof be strong enough to hold solar panels (or would it
have to be reinforced which would probably blow the economics out of the
water) (the roof is strong enough to walk across carefully for
occasional inspection purposes; 1980s build)

It may well be the case that Building Control should be involved.
At the very least, you would need them to confirm in writing that
they were content for you to proceed (2), otherwise a formal
application would be necessary.

(1)
The limit is 200 mm above the roof, except for Scotland where
they can be up to 1 metre above a flat roof, but not within 1
metre of the edge.
http://www.energysavingtrust.org.uk/...ing-permission

(2)
I made it a condition of accepting my installer's quote that they
supplied written evidence that Building Control were content,
before work started. If it had gone to a full application, they
would have dealt with it, simply passing on any statutory
charges.

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

Allan wrote:
Following on from the Solar PV panel thread (very useful info, thanks to
all contributors), I don't have a south-facing roof. However, I have a
flat garage (felted) roof which would be well positioned. Is it possible:

(a) that there are solar panels that come with stands so can sit on a
flat roof

(b) that the roof be strong enough to hold solar panels (or would it
have to be reinforced which would probably blow the economics out of the
water) (the roof is strong enough to walk across carefully for
occasional inspection purposes; 1980s build)

TIA
Allan

Allan, If you want to 'decode' my email address and send me a mail, I
can send you a document with info on the effect of efficiency of PV
panels when used outside the optimum angle which is 30-40 degrees elevation.

Bob

Bob Minchin wrote:

Allan, If you want to 'decode' my email address and send me a mail, I
can send you a document with info on the effect of efficiency of PV
panels when used outside the optimum angle which is 30-40 degrees elevation.

If you have a look at
http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php

Then you can personalise your location and most other criteria,
and see how this influences the output.

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

On Jun 14, 9:41*am, Allan wrote:
Following on from the Solar PV panel thread (very useful info, thanks to
all contributors), I don't have a south-facing roof. However, I have a
flat garage (felted) roof which would be well positioned. Is it possible:

(a) that there are solar panels that come with stands so can sit on a
flat roof

(b) that the roof be strong enough to hold solar panels (or would it
have to be reinforced which would probably blow the economics out of the
water) (the roof is strong enough to walk across carefully for
occasional inspection purposes; 1980s build)

Is theh garage attached to the house? Could the hopuse wall be the
anchor point for the higher edge? could the roof be replaced with a
stronger sloping one?

Why do you want solar PV?

MBQ

On Jun 14, 9:41*am, Allan wrote:
Following on from the Solar PV panel thread (very useful info, thanks to
all contributors), I don't have a south-facing roof. However, I have a
flat garage (felted) roof which would be well positioned. Is it possible:

(a) that there are solar panels that come with stands so can sit on a
flat roof

(b) that the roof be strong enough to hold solar panels (or would it
have to be reinforced which would probably blow the economics out of the
water) (the roof is strong enough to walk across carefully for
occasional inspection purposes; 1980s build)

TIA
Allan

Solar panels can be fitted to flat roofs. If they are horizontal they
will be considerably de-rated as regards output.
Given this,it's normal to fit them on a little slopey stand to incline
them somewhat to the South as it makes a considerable difference.

They need to be shadow free as far as possible.

The real trick is to keep the rooof waterproof.

As to the strength, who can say without inspection?

I have tables for outputs and deratings for non-ideal positions/
orientation.
PM me if you want them.