How to price up underfloor heating??

[Lillpete]

A builder I work for quite regularly has asked me to give him a rough price to supply and fit electric underfloor heating in a roughly 4m X 4m square room.

It's not actually going to need doing until around easter time, and I'm happy that he won't hold me to the price, he just wants a ball park figure so he can start putting some figures together, ignoring the actual supply for the moment as there will be other electrical work to do and this can be incorporated into that.

I've never installed u/f heating before so don't really have any idea what make/system to use or how long it will take to install, any guidance would be gratefully received ; )

 

[ian932]

Most of them these day's are a matt that has a sticky mesh built in I did a garden room last month took no more than an hour to roll out 2 mats and fit the thermostat sensor room was about 5.5m x 4m

 

[NozSpark]

I've just done a wire kit...

It came with a primer paint which it says reflects 20% of the downward heat back up.. that took 30mins

to put the wire down (3.5 sq meters) took about 1 1/2 hours and it was a nightmare on a concrete floor, the tape didn't want to stick... will take a hotglue gun next time!!!!

I did a mat kit a few months ago in a bathroom and that was an absolute nightmare.... mats are great for square rooms, but an absolute pain for anything else

BTW the 3 to 4 sq meter (600w) wire kit cost

 

[kme]

I've just done a wire kit...It came with a primer paint which it says reflects 20% of the downward heat back up.. that took 30mins

Its always good to do this day before, and let it dry. Also ensure no-one walk on it after the "green paint" phase, else the grey tape won`t stick (as you`ve found!!!!!)

to put the wire down (3.5 sq meters) took about 1 1/2 hours and it was a nightmare on a concrete floor, the tape didn't want to stick... will take a hotglue gun next time!!!!

Baaaaaaaad idea!. See above for tips regarding sticking after primer. Ensure primer is totally dry (in damp houses/weather, I`ve known it take 3 to 4 days!!!!!)

Also, if you`re fitting the wire, I`ll reiterate what the box says: NEVER remove the roll of wire from the box, it gets in a hell of a mess. Keep a rough measure of the length you`ve laid out, and when you`re 90% done, unroll to the cold tail (if the loop type), to allow you to get back to the other cold tail.........

I did a mat kit a few months ago in a bathroom and that was an absolute nightmare.... mats are great for square rooms, but an absolute pain for anything else

Agree totally. Also, some of the mats come in a roll, which doesn`t want to lay flat when you put it down. Tip: lots of "proper" gaffa tape, and a fair bit of time crawling around.

BTW the 3 to 4 sq meter (600w) wire kit cost

 

[Lillpete]

Thanks for the advice

I'm sure this is a stupid question but would I need 16m2 for a 4X4 meter room??

 

[batty]

Thanks for the adviceI'm sure this is a stupid question but would I need 16m2 for a 4X4 meter room??

Depends on what sort of room, ie furniture, you do not put it under kitchen cupboards and some furniture.

Batty

 

[NozSpark]

When I did the wire one in the week the client says "you will come back to make sure that it works??"

My reply was "yes, I've tested it just now and there's no reason why it shouldn't work... unless it gets damaged in between!"

 

[Evans Electric]

Lillpete , call into your wholesaler or go online , get the booklet for floor heating mats , buying guide in there for room sizes.

As said on earlier post , I power the mat up before tiles go down and get the builder to agree that, yes its getting warm. If they damage it they can't blame you . Don't leave it on too long.

Thing is , putting your meter across it means nothing to non-leckie types.

Deke

 

[kme]

n.b. Don`t forget to test the floor stat. too. They can be faulty out of the box........

If you`re using the wire, for a square 4m room, I`d probably use (wire wise) about 12m worth on the sizing chart, as actually fitting 16m worth in the room can be a bit of an issue.......

 

[NozSpark]

I think you are mean't to size on 75% - 80% of the room size!!

 

[kme]

To a point - warmup give you a room size, in sq. M. Then they`ll tell you the perimeter to leave, and the distance to leave between coils. However, I always used to find the figures incorrect; and downsizing their suggestions by approx. 80%, as you say, works better.