My brother will be starting an extension soon and he is considering
underfloor CH? Is it really as good as it claims to be?

I see various problems. The extension will be a bedroom with an ensuite over
his attatched garage.

1. He will be heating up the floorboards and probably a carpet before he
gets any heat, that must be a massive waste of energy. Would a good quality
wooden floor be better than a carpet?

2. Would I need to zone off the bedroom and ensuite seperately? I will zone
them off from the rest of the house regardless.

3. One thing we have considered is making the ensuite floor lower than the
bedroom floor so that UFH could be laid in a tiled screed above the
floorboards and it's finished level would be the same as the bedroom. Is
that feasible?

Adam

On Mon, 24 Mar 2008 17:09:38 +0000, ARWadworth wrote:

1. He will be heating up the floorboards and probably a carpet before he
gets any heat, that must be a massive waste of energy. Would a good
quality wooden floor be better than a carpet?

How is the energy wasted? Where does it go? Does it somehow get out of the
house?


--
John Stumbles

I used to think the brain was the most interesting part of the body
- until I realised what was telling me that

ARWadworth wrote:
My brother will be starting an extension soon and he is considering
underfloor CH? Is it really as good as it claims to be?

I see various problems. The extension will be a bedroom with an ensuite
over his attatched garage.

1. He will be heating up the floorboards and probably a carpet before he
gets any heat, that must be a massive waste of energy. Would a good
quality wooden floor be better than a carpet?


It not a waste of energy, it is just a time delay. Conversely the heat
in these will stay there after the heating goes off. A massive saving in
energy :-)


The key is to make the path to the cold places a lot better insulated
than the path to the places you want to heat! I.e. LOTS of insulation
under the pipes.



2. Would I need to zone off the bedroom and ensuite seperately? I will
zone them off from the rest of the house regardless.


Maybe. One tends to have sones anyway as all [pipes should be laid back
to a manifold. Its possible to e.g. put a TRV on a small zone.

3. One thing we have considered is making the ensuite floor lower than
the bedroom floor so that UFH could be laid in a tiled screed above the
floorboards and it's finished level would be the same as the bedroom. Is
that feasible?

definitely.

But beware of massive screeds on a suspended wooden structure. I would
rather go for a very stiff wood structure, with kingspan under the floor
and pipes just laid on top of that, and ply over. Then tile the ply.
Make that floor a lot stiffer than you would for carpet or
laminate..maybe 7" deep with herringbone braces..then there is plenty of
room for insulation and pipes as well.



Adam

"The Natural Philosopher" wrote in message
...
ARWadworth wrote:
My brother will be starting an extension soon and he is considering
underfloor CH? Is it really as good as it claims to be?

I see various problems. The extension will be a bedroom with an ensuite
over his attatched garage.

1. He will be heating up the floorboards and probably a carpet before he
gets any heat, that must be a massive waste of energy. Would a good
quality wooden floor be better than a carpet?


It not a waste of energy, it is just a time delay. Conversely the heat in
these will stay there after the heating goes off. A massive saving in
energy :-)

I think it might be worth doing. Especially as we can put all the needed bit
in in as we build.


The key is to make the path to the cold places a lot better insulated than
the path to the places you want to heat! I.e. LOTS of insulation under the
pipes.

So masses of kingspan then between the badroom floor and the garage.



2. Would I need to zone off the bedroom and ensuite seperately? I will
zone them off from the rest of the house regardless.


Maybe. One tends to have sones anyway as all [pipes should be laid back to
a manifold. Its possible to e.g. put a TRV on a small zone.

3. One thing we have considered is making the ensuite floor lower than
the bedroom floor so that UFH could be laid in a tiled screed above the
floorboards and it's finished level would be the same as the bedroom. Is
that feasible?

definitely.

But beware of massive screeds on a suspended wooden structure. I would
rather go for a very stiff wood structure, with kingspan under the floor
and pipes just laid on top of that, and ply over. Then tile the ply. Make
that floor a lot stiffer than you would for carpet or laminate..maybe 7"
deep with herringbone braces..then there is plenty of room for insulation
and pipes as well.

Room for thought. It should not be massive amounts of screed as this would
only be in the ensuite area.

Adam

"John Stumbles" wrote in message
...
On Mon, 24 Mar 2008 17:09:38 +0000, ARWadworth wrote:

1. He will be heating up the floorboards and probably a carpet before he
gets any heat, that must be a massive waste of energy. Would a good
quality wooden floor be better than a carpet?

How is the energy wasted? Where does it go? Does it somehow get out of the
house?


Eventually it will leave the house. But I am with you now.

Adam

On Wed, 26 Mar 2008 20:31:24 +0000, ARWadworth wrote:

I think it might be worth doing. Especially as we can put all the needed
bit in in as we build.

Have a look at the wiki article on UFH - I put in several links to
manufacturers' sites with some how-tos in there.

--
John Stumbles

Procrastinate now!

"ARWadworth" wrote in message
m...
My brother will be starting an extension soon and he is considering
underfloor CH? Is it really as good as it claims to be?

I see various problems. The extension will be a bedroom with an ensuite
over his attatched garage.

1. He will be heating up the floorboards and probably a carpet before he
gets any heat, that must be a massive waste of energy. Would a good
quality wooden floor be better than a carpet?

A waste of time. He will be heating up a garage as well. Best he heavily
insulates the floor between bedroom and garage and make sure is it
air-tight.

Myson Kickspaces can fit under baths thyat heat your feet - towel rails too.

Yes, zone off the new extension.

"John Stumbles" wrote in message
...
On Wed, 26 Mar 2008 20:31:24 +0000, ARWadworth wrote:

I think it might be worth doing. Especially as we can put all the needed
bit in in as we build.

Have a look at the wiki article on UFH - I put in several links to
manufacturers' sites with some how-tos in there.

--
John Stumbles

Will do. Time is on our side still as work will not start for a few months.

Cheers.

Adam

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember The Natural Philosopher
saying something like:

But beware of massive screeds on a suspended wooden structure. I would
rather go for a very stiff wood structure, with kingspan under the floor
and pipes just laid on top of that, and ply over. Then tile the ply.
Make that floor a lot stiffer than you would for carpet or
laminate..maybe 7" deep with herringbone braces..then there is plenty of
room for insulation and pipes as well.

The above would work ok, but with the addition of heat spreader ally
plates would work better.
--

Dave

Grimly Curmudgeon wrote:
We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember The Natural Philosopher
saying something like:

But beware of massive screeds on a suspended wooden structure. I would
rather go for a very stiff wood structure, with kingspan under the floor
and pipes just laid on top of that, and ply over. Then tile the ply.
Make that floor a lot stiffer than you would for carpet or
laminate..maybe 7" deep with herringbone braces..then there is plenty of
room for insulation and pipes as well.

The above would work ok, but with the addition of heat spreader ally
plates would work better.

Kingspan has ally foil on it. Its a moot point as to whether the cost of
adding more is worth the benefit. At this point I have no opinion.

On Sat, 29 Mar 2008 10:19:01 +0000, The Natural Philosopher wrote:

Kingspan has ally foil on it. Its a moot point as to whether the cost of
adding more is worth the benefit. At this point I have no opinion.

Question is whether you can get a significant amount of heat into the
kingspan foil by just laying the pipes on top of them. Otherwise
you're likely to have hotspots (or hot lines) in the floor.

I've been minded to try making grooves in the top surface of kingspan,
laying bacofoil over it and pressing 10mm pipe into it to warm the floor
of my loo. Will brag about it when/if I get Round Tuit and if it works.

--
John Stumbles

Things don't like being anthropomorphised.

John Stumbles wrote:
On Sat, 29 Mar 2008 10:19:01 +0000, The Natural Philosopher wrote:

Kingspan has ally foil on it. Its a moot point as to whether the cost of
adding more is worth the benefit. At this point I have no opinion.

Question is whether you can get a significant amount of heat into the
kingspan foil by just laying the pipes on top of them. Otherwise
you're likely to have hotspots (or hot lines) in the floor.

I've been minded to try making grooves in the top surface of kingspan,
laying bacofoil over it and pressing 10mm pipe into it to warm the floor
of my loo. Will brag about it when/if I get Round Tuit and if it works.


I definitely get hot spots even buried in 4" of screed.

Actually having pipes in an air mass under a suspended floor is probably
better to spread the heat,as micro convection will circulate the air around.

On Sun, 30 Mar 2008 12:09:05 +0100, The Natural Philosopher wrote:

I definitely get hot spots even buried in 4" of screed.

What's the spacing?

--
John Stumbles

The clairvoyants' meeting has been cancelled due to unforseen circumstances.

John Stumbles wrote:
On Sun, 30 Mar 2008 12:09:05 +0100, The Natural Philosopher wrote:

I definitely get hot spots even buried in 4" of screed.

What's the spacing?


Two squares on a rebar grid.

Its not noticeable in use, but it sure showed up when I was putting
levelling compound down.

The hot spots you can feel now are under the sofa :-)

On Mon, 31 Mar 2008 09:17:25 +0100, The Natural Philosopher wrote:

Two squares on a rebar grid.

Its not noticeable in use, but it sure showed up when I was putting
levelling compound down.

The hot spots you can feel now are under the sofa :-)

I notice the hot spots in our kitchen floor if I'm walking in bare feet.
Otherwise it just tends to feel comfortable in there most of the time,
unless it's really brass monkeys outside.

--
John Stumbles

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