Hi ...

I am about to buy and fit a conservation rooflight - thats a window
which is similar to a Velux but more expensive :-)

I have found four suppliers

Cast rooflight aka Clement Steel Window Co
Lumen
Metal window Co
Velux

The Velux offering can be quickly eliminated as the size is wrong for
me. The others all look quite similar and prices are comparable so how
do I choose?  I've never fitted this type of window before, so are
there any gotchas I should be aware of? Can anyone recommend any of
the companies listed, or suggest others? or comment on the quality of
the accompanying instructions - are they written for the benefit of
first timers? etc etc

Anna


-- 

            ~ ~            Anna Kettle, Suffolk, England  
 |""""|    ~            Lime plaster repair and conservation
 / ^^ \ //     Freehand modelling in lime: overmantels, pargeting etc
|_____ /                         www.kettlenet.co.uk

I can comment on the Velux GVT154 conservation roof window - having
had 6 of them fitted in the last month during a complete slate re-
roofing.

Comments are not terribly positive, having had to replace 5 out of 6
when my roofers found defects.

This Velux model has an aluminium framed window with a central
mullion, and hinges to one side to act as a means of escape window.

The problem was the plastic moulded surround, 2 had cracked right
through in the upper left corner, 3 more had hairline cracks in the
same place.

I suspect the problem was a poorer quality moulding caused by using
too high a proportion of recycled plastic. The replacements still feel
rather more brittle than I would like.

This model of Velux fits by sitting on top of the battens, which must
be recessed by 7mm (my roofers were grateful for me running custom
sections through the thicknesser for them). Upper and lower noggins
are also required and a sliding steel frame arrangement built into the
Velux should be screwed to these noggins.

This design would make them more difficult to fit retrospectively.

One other concern my roofers had was the built in lead flashing was
thinner than the stuff they usually use elsewhere.

On the plus side, the visual impact from outside the building is very
acceptable - they're in a highly visible location and blend in well.

So - overall advice based on my experience - ruthlessly inspect your
potential purchase, does it really look like that it will give many
years faultless service? What's the warranty like? What's the back-up/
manufacturers support/availability of a local rep like? (Velux were
good on this score). Ask how it fits retrospectively (I'm assuming
you're not doing a full re-roof). Ask how it fits with your type of
roof covering (slates, tiles - thatch???). How difficult would it be
to replace a broken sealed glazing unit? (With the Velux I would
probably buy a whole new one and swap it off the hinges). Do you have
underfelt on your roof? Does it work without underfelt if not? Does it
have a gas strut stay open? Will that work on the angle of your
roofline? What about strong winds? How would you repair other damage?
(With the Velux I think I would epoxy on a patch or flashing repair).

I'm bowled over by the quality of what my roofers have done,
particularly their leadwork - with hindsight I would have checked out
other window manufacturers and been willing to pay more - but I bought
on Velux's reputation (considerably reduced in my eyes) and the fact
that I had very tight size constraints on what was needed and the
GVT154 exactly matched those.

On Jul 5, 9:04 pm, n...@home.co.uk (Anna Kettle) wrote:
> Hi ...
>
> I am about to buy and fit a conservation rooflight - thats a window
> which is similar to a Velux but more expensive :-)
>
> I have found four suppliers
>
> Cast rooflight aka Clement Steel Window Co
> Lumen
> Metal window Co
> Velux
>
> The Velux offering can be quickly eliminated as the size is wrong for
> me. The others all look quite similar and prices are comparable so how
> do I choose?  I've never fitted this type of window before, so are
> there any gotchas I should be aware of? Can anyone recommend any of
> the companies listed, or suggest others? or comment on the quality of
> the accompanying instructions - are they written for the benefit of
> first timers? etc etc
>
> Anna

Fakro do similar conservation windows to the Velux, but in 4 sizes.
Haven't used them, but their ordinary roof windows are better and
cheaper than the equivalent veluxes.

A