On 4 Mar, 19:29, "Autolycus" wrote:

We've got a bedroom above the garage in our eight year old house
which
is always 5 deg C colder (or more) than the rest of the house on
cold
days. The fact that the bedroom floor is always cold leads me to
believe the insulation requires significant improvement between the
garage ceiling and bedroom floor.

snip

Could you put a suitably controlled larger radiator
in, or substitute a double for a single?

It's already a double.

With fins?

Yep, it has fins.

Larger rad = more load on boiler which is only
just the right size for a 4 bed house (cheap ass persimmon).

Is the boiler really running flat out, firing continuously, even on a
very cold day? I'd be surprised if the builder had calculated it that
closely. Older boilers can often have their maximum gas rate tweaked
(within defined limits, of course). Is it at its maximum rate?

Fair point, but the boiler already works hard to get the temperature
up. Thankfully the rest of the house is reasonably well insulated (as
you would like to expect for a house of this age) and the boiler will
not need to fire again for quite a while due to heatloss. I'm not
going to mess with the gas rate.


snip

It's true that insulating the floor will raise the temperature of its
upper surface, but I'm suggesting it may not be enough to raise the room
temperature much. The world acts as a heat sink for your roof and
walls, too, but you design accordingly.

I understand the basic physics of heat transfer and the fact that any
form of energy will want to take the path of least resistance to reach
a lower value. The most fundamental thing I also realise is that these
days, the houses which are bulk built by the big boys of the housing
estates like mine will only pay the minimum necessary to get a house
to stand up, pass the regs, and sell. That means using materials which
might be lesser to the ones we would choose.


So do the sums:
snip
Then
compare the cost with that of providing extra heat input, even if you
have to use supplementary heating occasionally.

Again, your point is simple and correct. Over time it'll probably be
cheaper to add supplemental heating. But sometimes, if a job's worth
doing, it's worth doing right. The concept of supplimental heating
doesn't give me that fuzzy feeling inside. I'll always feel like I
should have done the job properly.

This discussion is of great interest. But I'm still waiting for
someone to actually reply with "I've done to my house and it was/
wasn't worth the effort" which would prove or disprove if the job's
worth pursuing.

Thanks for everyones replies so far.

Jon