Central Heating

[st3v3]

Many thanks for your help again, and for your patience...!
I'll print the provisions off and find a darkened room to go study them.
I used to think that building decent homes must be tough work; it's actually probably quite easy - it's making sense of the regulations that's the real killer.
Thanks again.
regards steve

 

[st3v3]

So builder visited our house. He says that house design was accepted by buildings inspector in Dec 2006, so 2006 regs are applicable. In summary he say's :-

1. On the floor area which is 161sqm total, he says usable area is only 145sqm as stairwell and cupboards aren't usable. Is that right?!!?

2. As 145sqm is less then 150sqm, he only needs to have single thermostat in main zone and TRVs elsewhere. Is that what Domestic Heating Compliance guide means by " Dwellings with a total usable floor area upto 150sqm should be divided into at least two space heating zones with independant temperature control.."? Is each room with a TRV fitted what the DHCG means by 'a space heating zone with independant temp control'?

Would appreciate some advice if you can find more time for me.

regards
Steve

 

[Dan Robinson]

I wish I had so little to worry about in my life.


Courtesy of Charnwood:

http://www.consumers.randall.danfoss.co.uk/PCMPDF/039v01.pdf

 

[Dan Robinson]

Ok then .... I can offer you some controls for you extra 6 sqaure meters if you like?

You do realise that is smaller than a large bed don't you?

P.S. Charnwood gave you the answer...I merely repeated it as it seems you still need some things to worry about....


*sigh*

 

[kevplumb]

another satisfied customer dan

 

[sooey]

cucukachoo mr Robinson, stevie loves you more than you will know......whoa whoa whoa

 

[Dan Robinson]

Sad no... stuffed to the gunnels with fine cheeses from din dins yes.... and I still can't bring myself to worry about 6 metres of wasted heat.

But as I said... Charnwood has given you the info you wanted. I confirmed this for you.

And yet you haven't thanked either of us.


Genii often go unappreciated .

 

[Agile]

Many famous people only become famous after they have died!

OP, you should be running your boiler flow temperature at about 70 C or lower ( not 80 C as you mentioned ).

Convenient being in Hull so that Ideal can pop over the same day each time it goes wrong!

 

[mysteryman]

You can do yourself a considerable favour by equipping your heating system with weather compensation. This varies the radiator flow temperature inversely with outdoor temperature. As well as savings from reducing temperature overshoots, the boiler will be kept in condensing mode for nearly all of the heating season. Savings can be as much as 15%.

 

[D_Hailsham]

In summary he say's :-

1. On the floor area which is 161sqm total, he says usable area is only 145sqm as stairwell and cupboards aren't usable. Is that right?!!?

No!

Approved Document L1A uses the word 'useful' which somehow has become 'usable' in the Guide. (In this context they mean the same thing).

L1A says that 'useful' is defined in the relevant EU Directive.

According to the DCLG (Department of Communities etc) website:

The Total useful floor area is defined as the total area of all enclosed spaces measured to the internal face of the external walls. Included are areas of sloping surfaces such as staircases ... where the area taken is from the area on the plan. Excluded are areas that are not enclosed such as open floors, covered ways and balconies.

As 145sqm is less then 150sqm, he only needs to have single thermostat in main zone and TRVs elsewhere. Is that what Domestic Heating Compliance guide means by " Dwellings with a total usable floor area up to 150sqm should be divided into at least two space heating zones with independent temperature control.."? Is each room with a TRV fitted what the DHCG means by 'a space heating zone with independent temp control'?

You need to read on further in the Guide! See Table 2 - "Temperature control of space heating". This says you have three options:

1. Room thermostats or programmable thermostats in all zones; or
2. A room thermostat or programmable thermostat in the main zone, and individual radiator controls such as TRVs on all radiators in the other zones; or
3. A combination of 1 and 2.

So if your total internal floor area, including cupboards and the floor space occupied by staircases, is less than 150sqm you only need a room thermostat and TRVs on all radiators other than the one controlled by the room stat. Over 150sqm you need to have two zones with separate time and temperature controls.

 

[Agile]

Over 150sqm you need to have two zones with separate time and temperature controls.

I thought you said elsewhere that the requirement for two zones when over 150 sq m was dropped a couple of years ago?

 

[D_Hailsham]

Over 150sqm you need to have two zones with separate time and temperature controls.

I thought you said elsewhere that the requirement for two zones when over 150 sq m was dropped a couple of years ago?

I hope I didn't say that as it's wrong.

Current requirements as set out in the Domestic Building Services Compliance Guide 2010 are quite clear:

Up to 150sqm: 2 zones with separate temperature controls
Over 150sqm: 2 zones with separate time and temperature controls

The only exception is for single storey dwellings where the living area is over 70% of the floor area. In this case only one zone is required. This could cover anything from a bedsit to a large open plan loft in a converted warehouse.

While nothing has really changed for over 150sqm cases - it will require a S Plan Plus system, ie zone valves on each heating zone - under 150sqm requirements have changed from those in the 2006 Guide.

2006: Two zones - room stat in one zone, TRV elsewhere (option 2 in my last post)

2010: Two zones - room stat in main area of each zone, TRVs elsewhere. (i.e only 2006 option 3 in my last post)

This effectively means that you have to have two zone valves for both over and under 150sqm. The only difference is that under 150sqm you need just a single timer and two thermostats; over 150sqm you need two timers and two thermostats.

 

[st3v3]

I thank you again D_Hailsham for your time and accuracy of answer...really helpful.
I see I have a bit of a battle on with the builder who is clearly backpedalling, as he's put an S Plan Plus in smaller houses than ours on this development. I've started the resolution process with NHBC as well so hopefully we'll get the system that I believe we should have.
Many thanks again for all your time and effort - you're a credit to the website and the industry!!!
regards
Steve