Insulation issues in new build home

markin

Did you give heating the house for some days a go, To see if the usage started to drop as the house heated up fully?

FreeBear said:

Panda126 said: Our house is losing heat ridiculously fast, for example we can heat up a room up to 20C. The moment we turn off the radiators our temperature starts to drop. We calculated that it is dropping by 0.5C every 20-25 minutes.

For a new build, that is terrible and more than twice the temperature drop I get in a late 1920s semi. Last night, the temperature outside was around -1°C, and I experienced a drop of about 0.39°C per hour (went from 20.5°C to17.8°C in 7 hours).

With a 1°C/hr drop, I'd be having some very stern words with the developer, and if no action on their part, looking at legal action. If the developer tries to deny a problem exists, get a professional thermographic survey done to pinpoint the cold spots and use that to beat the developers around the head. Whilst your thermal images demonstrate that there appears to be a problem, a report from a qualified/certified expert carries much more weight (important when it goes to court).

From the first post on the other thread, That may be heatloss from only heating 1 room to 19c, So the loss to the rest off the house from an internal door and un-insulated ceilings will be high.

As the house was mostly un-heated a thermal from outside may not tell us much.

 
 

markin

Have you fitted Curtains for energy efficiency? Electric panels should be very easy is move over a little.
   https://forums.moneysavingexpert.com/discussion/6498860/curtains-for-energy-efficiency


And i'll say it again get a split A/C heating unit.

QrizB

Thanks for the info.

My 1950s brick-built semi with retrofitted cavity wall insulation and less loft insulaton that I really should have  heats up slightly slower than yours does, but it cools much more slowly. We're currently getting through 60kWh of gas a day and out thermostat set points are a little lower than yours (14C at night, 18-19C day).

The inspection from outside should show hotspots clearly.

I remember a new article from a litle while ago (sorry, can't find a link) about a new-build estate that had unexpectedly high energy costs. Thermal imaging showed that some walls were missing their cavity insulation.

Panda126

We're on agile tariff and electricity was very cheap over few days during Christmas so we gave the house a full blast of heat for a few days, it's not like we won't heat the whole house. We set radiators on minimum 17 at night. But doesn't matter how much time we'll be heating it up or what temperature, it will always drop very fast once we turn the heating off. 

Reed_Richards

I live in a cavity walled bungalow built in 1980.  The only part with some thermal mass is the solid concrete floor, about 15 cm thick, a very thin layer of polystyrene below, and a thin layer of insulating material on top.  The loft has fibre wool insulation, mostly to the height of the rafters but with another layer on top over about 1/3 of the loft area (ongoing project).  None on the inside walls are solid. 

Our heating went off at 22:30 yesterday and the living room was at 20.5 C.  It had fallen to 18 C by 03:30 so that's 0.5 C per hour.  It was about -4 C outside overnight.

When the heating came on, the building warmed up at about the same rate, 0.5 C per hour, but it's set to warm up economically rather than as fast as possible.

markin

What were your outside temps and energy use for the days you heated?

Its normal for the windows to be 5c lower that the walls, And some of the cold corners on the walls could just be damp from being a new home, External photos taken after sun set should show if the is insulation missing in places.

I'm also using 60-80kwh electric in a 1950's house, it would simply have been cheaper if on Gas or 3 years ago.

RelievedSheff

As asked in the other topic you started did you ever allow the house to fully warm up. and fully heat through?

You were only heating one room previously so your heat losses would be to the other unheated areas of the property.

It is perfectly normal for windows to be colder than the walls of a house. They are a couple of panels of glass panels rather than a heavily insulated wall.

Panda126

I took some photos just now and it seems that the bottom of the house is 'glowing', close to the windows and the garage door. Also not sure why but the windows upstairs are dark but not the windows downstairs?

MultiFuelBurner

I believe the scale is important there the top is 3.6oC/5.8oC that's not as glowingly hot as the pictures may suggest. 

(I may be wrong here so correct me someone if this is the case)

jimjames

FreeBear said:

Panda126 said: Our house is losing heat ridiculously fast, for example we can heat up a room up to 20C. The moment we turn off the radiators our temperature starts to drop. We calculated that it is dropping by 0.5C every 20-25 minutes.

For a new build, that is terrible and more than twice the temperature drop I get in a late 1920s semi. Last night, the temperature outside was around -1°C, and I experienced a drop of about 0.39°C per hour (went from 20.5°C to17.8°C in 7 hours).

Our house is similar (1930s) at 0.44C per hour so I agree that it's shocking a new build would be worse. It's very noticeable that our extension built in the last 10 years is warmer than the main house so I would expect new build to be same.