Is it worth getting an extra radiator?

chockydavid1983

Hey guys

I just bought a house about a month ago and noticed that on a couple of mornings where I was in waiting for deliveries that I had to turn the heat up quite high in the lounge to feel the effect.
It's a fairly big room and there's currently one large radiator (140mm) by the front window and a smaller one (100m) near the end of the RHS wall if looking from the front.

I was wondering if having an extra radiator near the start of the RHS wall would mean that I could then get the same heat generation from a lower setting all round and better distributed around the room? I'm not really sure how this kind of thing works.
The other option is under floor heating as I'm planning to replace that at some point or I'm open to other suggestions.
I have a modern combi boiler (installed 2011). If you need any more information to give advice let me know.

Thanks,
Chris.

Smiley_Dan

More radiators mean more heat emitted into the room, yes. You would have to ensure the kW rating of the boiler covers all the rads. It *probably* does, because a heating engineer would normally fit with plenty of room to spare, but that might depend on whether other rads have been added.

Using this: http://www.simplifydiy.com/plumbing-and-heating/radiators/power you could estimate the total kW draw of all of your rads and then compare that to your boiler rating.

But now to answer your question in a different way:

It would worry me a bit that you already have two rads and the rooms is not warm. First you can try the normal stuff - making sure the rads are bled and are warming up properly.

Next I would look at the heat loss from the room. This is what I'd do if my rads were working ok. Solve any draughts and look at how heat might be lost from the room - through the walls, floors, ceiling and openings.

Adding a radiator will also cost you more long term because that's more water to heat.

chockydavid1983

Hi Dan

Thank you for your reply.
I will check the kW rating of the boiler later.
I don't believe it's a problem with the rads as they were hot all the way over.
I think I had to turn up the thermostat to around mid 20s for it to feel warm in there when in my head I was thinking more like 20 should have been sufficient or maybe I have unrealistic expectations and it depends on room size etc?

Thanks for the other suggestions, I hadn't thought about how much they may factor in.
I did notice on my EPC report it mentioned that it is assumed there is no insulation under the flooring so I am planning to add that if I don't have it when I replace the flooring so I guess that would make quite a big difference.
The windows are also fairly old, around 10 years I think and I was planning to replace those also at some point so I guess that would also make a difference.

I've been looking into the pros and cons of underfloor heating and it seems that it is fairly expensive to install and would take a long time to gain back in savings but it does help to heat the room more evenly and at a lower temperature setting.

Thanks,
Chris.

Cardew

It is pretty certain that the combi boiler will cope easily with the extra heating load for radiators, as the boiler maximum output is for the domestic hot water.


If the small radiator is single panel, and a standard size, you can simply replace it with a double panel; or if a double panel, a triple panel. That way it is a very simple DIY job without the need to alter piping.

Smiley_Dan

The "normal" temperatures are for a lounge at 21, bedrooms at 18 but it depends on what you want/need obviously. Thermostats can also be broken. You could test with a thermometer.

The amount of energy required to heat a room obviously depends on the room size.

What sort of floor do you have, is it solid or suspended? I.e. is it concrete or floorboards over a void? The latter is common in older properties and can be a big source of heat loss.

UFH can be a good move but I think it's best done in solid floors. So take the time then to fill in with concrete and insulate to the max.

Draught proofing is the cheapest way to reduce heat loss to take a look for any source of draughts, e.g. windows, between the skirting and the floor (if it's a hard floor) under window sills, between walls and window frames, window to frame gaskets etc. Holes in the ceiling cut for downlighters (horrible things). Also obviously if there's a door open and an unheated space there it won't help.

HappyMJ

chockydavid1983 wrote: »

Hi Dan

Thank you for your reply.
I will check the kW rating of the boiler later.
I don't believe it's a problem with the rads as they were hot all the way over.
I think I had to turn up the thermostat to around mid 20s for it to feel warm in there when in my head I was thinking more like 20 should have been sufficient or maybe I have unrealistic expectations and it depends on room size etc?

Thanks for the other suggestions, I hadn't thought about how much they may factor in.
I did notice on my EPC report it mentioned that it is assumed there is no insulation under the flooring so I am planning to add that if I don't have it when I replace the flooring so I guess that would make quite a big difference.
The windows are also fairly old, around 10 years I think and I was planning to replace those also at some point so I guess that would also make a difference.

I've been looking into the pros and cons of underfloor heating and it seems that it is fairly expensive to install and would take a long time to gain back in savings but it does help to heat the room more evenly and at a lower temperature setting.

Thanks,
Chris.

The thermostat might not be working properly. I'd get a thermometer to check the temperature in the room that you're in. They aren't always very accurate so if you set it to 25 in the room with the thermostat it might only be 20 degrees or so in the lounge. A properly set up and balanced system should have the bedrooms slightly cooler at 18 or so.

Cardew

chockydavid1983 wrote: »

The windows are also fairly old, around 10 years I think and I was planning to replace those also at some point so I guess that would also make a difference.

I've been looking into the pros and cons of underfloor heating and it seems that it is fairly expensive to install and would take a long time to gain back in savings but it does help to heat the room more evenly and at a lower temperature setting.

Thanks,
Chris.

10 year old windows needing replacement?? Even if they are single glazed, the cost of replacement is so high that it is never an economic proposition.


Ditto, as you suggest, for under-floor heating. Whilst it is true you can have a lower heat setting, what about rooms without underfloor heating? bathroom etc. It could mean that the radiators will not provide sufficient heat.

chockydavid1983

Thanks for your replies guys.
I'll check if the small radiator later and check the room temperature against a thermometer. It's a mobile thermostat so when I was checking previously I had it on the windowsill in the lounge.
It looks like and is a solid floor according to the EPC.
I will look at draught proofing. There is an adjacent unheated kitchen with no door so I guess fitting a door there would help? Or adding a rad in the kitchen?
The windows are double glazed and are 3/5 stars on the EPC. The only reason I was thinking of getting new ones or perhaps triple glazed is as the majority of the other things listed are 4/5 stars so it seemed a weak spot (other than the lack of floor insulation, which was the big one mentioned).
I was only thinking about under floor heating as an alternative really and possibly doing it as I was replacing the flooring. But it does sound there are many other factors to consider first.

Thanks,
Chris.

Smiley_Dan

The window sill might be one of the coldest parts of the room because of the convection currents next to the window. Air hits the window, cools because it is a colder surface and sinks. Try having it elsewhere. Which direction does the window face? If it's north this might be the problem.

Depends on how much window area you have but you probably won't see payback for a long long time going to 3G. As ever, it depends on your situation, so you need to do the heat loss calculations yourself.

chockydavid1983

Ah OK, thanks Simon. I believe it's North facing as I get Sun in the early part of the day in the garden and my lounge is at the front.
Looks like I need to do some more testing before changing anything .

CashStrapped

Hello


What age/type is the property?

Firstly I concur with Cardew, 10 year old windows are not old, nor will the cost of replacing what are probably already efficient (double glazed) windows, with slightly more efficient windows be worth it. It may take you 20 - 30 years if not more to see your money back.

I blame upvc companies. They have managed to slowly convince the population over the years that windows should be considered "white goods" and replaced often! Ludicrous in my opinion.

For context, I have large period single glazed bay windows (so a large surface area). I have no problem in maintaining a decent room temperature with the thermostat set to 17-18 degrees. Now all houses are different, but I am very much sure that replacing the existing double glazed windows should be the very last thing on the "to do" list.

Only if the windows are very poorly fitted (visible gaps), with failed seals (moisture between the panes) would I even consider replacing them.

I read on a lot of forums homeowners assuming the more costly fixes will always solve the problems. However the majority of the time it is the small cheap changes that can make all the difference.

What make and model of boiler? How is it set up? When was the boiler last serviced? When was the heating system as a whole last serviced? How quickly do the radiators heat up? What is the output temperature of the boiler set to? As others have mentioned, check the thermostat.

Other things to look at; is the room carpeted? Good underlay? Is the house solid or cavity wall? Are any walls in that room exterior walls? Would you consider cavity wall insulation?