I'm not sure if this is entirely the right group, but here goes...

We've got this old chapel, and the roof (most of which is overhang) is
barely insulated, certainly nothing near any standard. The only way to
do it is to take the tiles off. It needs doing, and unfortunately as
there's virtually no loft, there aren't any grants (or not that any of
the grants people are telling us).

Also, I thought the VAT level on work primarily for insulation (and
thus carbon reduction) was 5%? But the quotes are at 15%.

Anyway, we had one quote we can blow straight out with a good laugh of
£23,000. However, the only other two that can really do much before
winter are coming in at £16,000 and £18,000 including VAT.

This is WAY more than we were expecting - but the fact that the two
were so close...does that suggest that basically, that's what the
price is?

If you're feeling bored or brave, I've posted the spec that went out
for quotes. Yes, there's a lot to do - they think about a month - but
still .... £16,000?!? (That's assuming we can actually borrow that
much!). We were thinking £10k inc, max. Or were we living in cloud
cuckoo land?

Anyway.....

Starting with rear roof, strip down to top of outshot and save good
small slates for front surface of roof.

Remove top few rows of slates at top of outshot roof to ascertain
insulation levels below. If insulation is inadequate [TBA] then whole
surface to be stripped and new insulation fitted as below. Price to be
submitted for this as a separate item.

Check all structural timbers for rot or worm and treat or replace bad
areas as necessary.

Replace facias and barge boards as necessary. New or existing facias
to be topped off with 25mm deep [or as required – see 6 below]
ventilation strip. This increase in height will facilitate the fitting
of counter battens on the roof surface and a tilting fillet. New
facias and barge boards should be naturally durable timber such as
Western Red Cedar, Douglas Fir or European Larch.

Insulation on main roof:

Above sloping ceilings fit maximum possible thickness of rigid closed
cell foam insulation such as Kingspan, i.e. to depth of rafters. This
must be tightly fitted and any gaps between insulation edges and
rafters filled with foam or mastic to prevent heat loss as a result of
small convection currents. Insulation to extend over tops of walls.

On horizontal ceilings insulation will be installed to a depth of
250mm when roof is watertight. Insulation to be mineral fibre or
equivalent 'non-itch' type or Warmcell. Latter would have to be
installed by specialist contractor. Please provide prices for all
options. Insulation should not extend under tanks or pipe runs. These
should be insulated above and on the sides with appropriate materials.

All roof space and sloping ceiling electrics to be checked by
qualified electrician and remedial work carried out before insulation
is installed. New cable runs for e.g. new light positions, to be
discussed with clients and installed. Electrician's written statement
to be provided when work is compete.
Breathable membrane to be fitted over entire roof surface and held
with vertical treated battens.

Fit horizontal treated battens at spacing required for slate type as
described below. Tilting fillet to be provided for first course.
Dormers??

Slating. Good small slates as existing to be used for front elevation.
Utilise those salvaged from rear and purchase additional s/hand as
required. Fix with copper nails. Rear roof can have larger slates to
match those on outshot. Purchase new or s/hand as necessary. .
Vented ridge. Type TBA.

Soffits – FSC ply or as agreed.

Paint all facias and soffits. Paint type and colour TBA.

Rainwater goods. If minimal replacement required then use existing
type. If extensive replacement required then type is TBA.

Lead valleys and flashings. Use Code 4. Valley lengths not to exceed
1200mm. Chimney cover flashings to be held in place with lead rolls
and suitably pointed.

Check and renew chimney pointing, haunching and cowls as necessary.