Radiators placed under windows??

paddy147

My mate and his wife are in the process of a major house rennovation job(old 1930s house stripped back to just 4 bare walls)

Myself and my mate were chatting today about the radiator locations and where they were going.The double glazed windows went in today,so next up is the radiators.

All of them,except for 1 rad are going under the windows in each room in the house.

So is it ok for rads to be fitted under a window??

Just curious to know what anyone thinks.

Thanks.:)

Poor Uncle Tom

Some recommended reading.

paddy147

Poor Uncle Tom wrote: »

Some recommended reading.

Thanks.

So rads under the windows is fine then.

Poor Uncle Tom

I've always thought so.

paddy147

Poor Uncle Tom wrote: »

I've always thought so.

Good to hear and read it so.

My mate will be happy to read that link too.:)

DUB777

Have a read of this.

http://uk.answers.yahoo.com/question/index?qid=20091007105534AAmFvaG

Poor Uncle Tom

paddy147 wrote: »

Good to hear and read it so.

My mate will be happy to read that link too.:)

What's your opinion, Paddy?

DUB777 wrote: »

Have a read of this.

http://uk.answers.yahoo.com/question/index?qid=20091007105534AAmFvaG

67% for and 33% against.

The main arguement for not having the radiators at the windows is:

In the eighties, a team from the "Tomorrows World" series on BBC (UK ) went out on a cold winters nite arned with infra-red cameras. They went to a typical housing estate and took images of a typical street. They were alarmed , but not surprised to find hot spots under most windows.
The presenter of the show Raymond Baxter concluded that the situation was not acceptable.
He said...... why don't architects, builders, heating engineers, plumbers, and anyone else who is interested in installing wet central heating. ( radiators ) place them where it is not possible to place furniture, and allow the householder to have long curtains /drapes as they please.
Suggested places include behind internal doors. alcoves etc.
10 years plumbing and NEVER put a radiator under a window.

What was the level of insulation in the houses 'tested'? I would say that wherever a radiator was placed in any of those houses an infra red image would pick up a very hot spot in the wall outside it, regardless of whether it was under a window or not because of the poor level of insulation throughout housing in the 1980's.
That little 'experiment' proves nothing about radiators or their positioning, but it is a damning inditement on the levels of insulation and airtightness in 1980's housing, and there has been incredible leaps forward in the development in those areas in the past 30 years. Yet even with all the developments in building technologies over the years, radiators are still being positioned under windows, could it be that it's the best position for them, and the areas that actually needed developing has been developed?

Finally if a plumber has been putting in radiators for 10 years and given that nearly all drawings with radiator heating systems show the rads under windows, how is it that this person has NEVER put a rad under a window?

paddy147

Ive no opinion,because every time I give my orinion,I usually get an infraction,banned for 7 days or banned for a month(.lol):pac:

Poor Uncle Tom

paddy147 wrote: »

Ive no opinion,because every time I give my orinion,I usually get an infraction,banned for 7 days or banned for a month(.lol):pac:

Naw, 10 days is the shortest ban I've given you....:p

Seriously, you started the thread, surely you have an opinion....:)

paddy147

Poor Uncle Tom wrote: »

Naw, 10 days is the shortest ban I've given you....:p

Seriously, you started the thread, surely you have an opinion....:)

Im not a plumber or a heating expert so I wouldnt be qualified to give a propper opinion.

muffler

paddy147 wrote: »

Im not a plumber or a heating expert so I wouldnt be qualified to give a propper opinion.

That's a CYA answer.

Dave_Geoghegan

Under the window is fine, in fact placing a rad under a window reduces heat loss through the window by creating an imaginary curtain of hot air rising up from the rad.

jimmycrackcorm

Many years ago I worked on a software program for laying out piping systems for a pump manufacturer. The program specifications were that by default radiators were to be placed under windows. When I questioned the rationale I was told it was due to increased air convection for heat distribution.

If the windows are double-glazed then I guess that is of less relevance now.

slavetothegrind

under the windows is good as long as you don't have full length heavy blackout curtains covering the rad.

more flexibility in a properly insulated house and should be incorporated in the design aspect of the rooms to minimise difficulty with furniture placement etc.

Kitchens are a classic example where a plumber might go for the obvious spot for him/her it might impede the placement of a large american style fridge for example. ( yes my house:rolleyes:)

paddy147

The only problem with the radiator under the front window in a sitting room though is the fact that you cant use full length curtains,for that very reason above.

On the other hand,Id say that if the house is well insulated than it would be good to have rads under the windows.

The plumber told my mate and his wife that the rads would be best suited to under the windows in their house,as their house is also internally slabbed out with insulated plasterboard and 300mm attic insulationHe and his wife seem happy enough with the rad locations.:)

My own house is done like this (rads under windows and internal insulation on all the walls.Im going for the spray foam insulation in the attic next Friday.

Poor Uncle Tom

The only problem with the radiator under the front window in a sitting room though is the fact that you cant use full length curtains,for that very reason above.

In Design a couple of rooms have traditionally challenged the notion that rads should be placed under windows, those are the kitchen as the sink is normally under the window and the sitting room as the window there can be a bay with a very low cill. Nobody is saying that you MUST put the rads under the windows, we are just saying that traditionally it is the best location for them.

Regarding the curtains, I think design comes into play here as well, do you remember the old hospital radiators? they were freestanding, there is nothing wrong with the idea of designing a freestanding radiator for your sitting room which is placed say 75mm clear of the wall to allow for full length curtains to close behind it. It would also allow clear space to clean behind the radiator.

On the other hand,Id say that if the house is well insulated than it would be good to have rads under the windows.

Conversely, I would say the better insulated the house is the less need there is to place rads beneath the windows.

The plumber told my mate and his wife that the rads would be best suited to under the windows in their house,as their house is also internally slabbed out with insulated plasterboard and 300mm attic insulationHe and his wife seem happy enough with the rad locations.

My own house is done like this (rads under windows and internal insulation on all the walls.

Not withstanding what I've said above, I suppose regardless of how well a house is insulated a glazed area is always going to be thermally less well off than a well insulated wall causing temprature variations falling back to the original theory of having therads under the windows as it is the coolest area....:p

Im going for the spray foam insulation in the attic next Friday.

I got that from the other thread, in fact I think I might have deleted it a few times....:D

Dubstar07

It is more effcient to place radiators under windows. THe window is the weak point in terms of the heat loss through the building fabric.
for calculation purposes the window has a u-value of around 1.6 but will vary with the type of glazing, frame. The wall on the other hand is currently about 0.25 (u-value) - if building to current regs.

The radiator uses convection to distribute heat aound the space ( as well as radiant heat) colder air will naturally be drawn to the window and it helps to circulate the heat in the space.