Calculating Rad BTU's and room plan (Plans Attached)

[brooky_agb]

Hi Folks,

I need to order some rads but I'm struggling to get hold of the plumber. I need to order them and I'm going away on holiday soon. I thought it would be great to get others opinion too.

I was going to give him the plans below. Do my calculations look reasonable and do you think it will work ok?

It's a new ground floor extension which is well insulated although the kitchen has a vaulted roof approx 3.4 meters at the highest point. The worktop shown by radiator A won't be there but we want a dresser leaving around 900/800mm space for a rad...

Any thoughts? Many thanks for taking the time to look.

p.s. The shower room is the same dimensions as the utility room.

 

[bengasman]

Leave the sizing up to the guy you pay to do it. If you get it wrong, you have no come back.
Too many variables to make using a standard heatloss any better than a rough approximation.

 

[brooky_agb]

Oh but I have been asked to do it from the start? I've just been told to supply radiators ready for the plumber who will fit them whilst I am away. I forwarded the plans to the building company to get them to take a look.

 

[bengasman]

Oh but I have been asked to do it from the start?

"plumbers" supplied by builders generally tend to be questionable. Builders are often more interested in which plumber leaves them the most mark up than which one does the best job.

If at all possible, take the heating side away from the builder and get a good RGI to take over from here.

Leaving the calculations to the householder is simply ridiculous.

 

[brooky_agb]

Ok... hmm what to do... I don't know a plumber who I can trust. The one we used last time was in prison for losing his Corgi!!

 

[bengasman]

Plenty good ones around, some cracking ones near you.
Takes a bit of effort though, asking all your friends, neighbours, colleagues etc for recommendations.

 

[brooky_agb]

Is it really that hard to work out what rads you need? There are 101 calculators online?

I'm grateful for your opinion but I don't really want to have to find a plumber and organise myself. I will though if thats what people recommend.

Many thanks for your help.

 

[bengasman]

Is it really that hard to work out what rads you need? There are 101 calculators online?

Like I said, too many variables that only become apparent on site, IF you know what to look for, to make theoretic calculations reliable.

 

[brooky_agb]

OK I understand. The thing is there are only two places we can have radiators. For this reason I think I just have to order the most powerful ones I can that fit. This will make approx 14,000 BTU.

 

[bengasman]

That should work; you can't really oversize a rad unless it is the one rad in the room with the roomstat.

4 kW is a fair size. As it is effectively new built, I presume insulation and draft proofing are sorted.

 

[brooky_agb]

The builders think we should go for electric underfloor heating instead.

I'm worried its horribly expensive to run. Saying that we hardly use our central heating as oil is so expensive!!

 

[RichieHoneybucket]

Ok... hmm what to do... I don't know a plumber who I can trust. The one we used last time was in prison for losing his Corgi!!

FFS!!!......I didn't think losing your dog was that serious???!!!!
Just cause the guy lost his dog, I don't think that's grounds not to trust him.
Mind you, if it was one of the queen's corgis I'd understand that.

 

[brooky_agb]

ROFL!!

 

[bengasman]

Dear mr Devellion, ( or is it MRS?? )

Your builder used a plumber who can't be asked to figure out what rads you need. Said plumber can't be reached either. They let you meddle on with the problem which indicates that they really don't care about the end result too much.

I have explained why you should not do the job yourself, how it can be solved, and what should be done.

After all this, you announce that in fact the builder recommends electric heating and does not want radiators in there at all.
Forgive me, but I am giving up on this one.

 

[brooky_agb]

Neither actually. It's my companies name.

I wish I could give up too. I might become a gypsy instead, live in a a caravan and thieve for a living.