SuperHome Database

London, Haringey, Muswell Hill, Grosvenor Road

House Summary

Stewart and Mary Mcilroy

House Type:
Edwardian 1900 end of terrace

Carbon saving:
61% - SuperHomes Assessed  

Reported saving on bills:

Total invested:

Smart Homes

  • Haringey- Grosvenor Rd Wood Stove
  • Wood stove at Muswell Hill SuperHome
  • Wood store fence
  • wood-storage1
  • wood storage 2smlcrop
  • garden 1smlcrop
  • stewart-fuel-box2-500w

Measures installed:

  • Ceiling insulation
  • Condensing boiler
  • Draught-proofing
  • Floor Insulation
  • Internal Wall Insulation
  • Loft Insulation
  • Low Energy Lighting
  • Secondary glazing
  • Solar PV Panels
  • Solar Water Heating
  • Water Saving Devices
  • Wood Stove

Upcoming events

Early interest in Open Days encourages SuperHome owners to host more events. If you'd like to visit this property please contact the owner and let them know. SuperHomers are often happy to respond to questions about their refurbishment project by email between times. Please read ‘more on contacting this SuperHomer’ before you make contact.

What visitors are saying

"The home owner had a very knowledgeable and hands-on approach to the improvements he had made. We were very interested in the insulation changes he had made."

“Very informative visit, enthusiastic home owner, we learned several possible ways of reducing heat loss from our home. All very practical and helpful.”

“Really grateful to Stewart and his family for their time, organisation and clarity of "the tour", very inspiring!”

"Enthusiastic and informative talk by the homeowner, full of specific practical advice, backed up with figures... several new ideas which we fully intend to implement."

"I learned a lot about what the owner had done to improve his home and how with an appreciation of the work involved."

"Clear, friendly, informative, intelligent and well prepared."

"A very informative tour. My house is similar in many ways so it will help me in the future with my own improvements. "

"Great practical advice which we can all do to improve our houses."

Personal story:

I have always been interested in environmental issues and see it as our responsibility to act sustainably in everything we do. Working towards an energy efficient house and wildlife friendly garden should be seen in that context. Over the years we have done more work on the house as our knowledge and money has allowed.


All of our family are interested in environmental issues including household energy efficiency, the countryside and wildlife. I also find DIY, using recycled products where possible, practical and fulfilling and a relaxation from my job as a management consultant. We have carried out the energy saving refit of our house for several reasons including comfort (a warm house is more comfortable than a cold house) plus doing the right thing in terms of reducing our carbon emissions. The energy efficiency renovation process has also been very interesting and satisfying. Helping others to reduce their emissions in a cost effective manner, including avoiding some of the blind alleys we went down, is also very rewarding

Property background:

Large (200m2) 1900 Edwardian end of terrace property over 3 floors including attic. Solid wall construction with 31 windows. All original features including sash windows, coving, wood floors and two fireplaces now with wood burning stoves.

Key changes made:

2 wood burning stoves (main one on ground floor)
New high efficiency gas boiler
Solar hot water
Solar PV
All windows with secondary glazing
All internal faces of external walls with internal wall insulation
Underfloor sheeps wool insulation
Continuous running heat recovery fan in bathroom

Measures installed in detail:

  • All internal faces of external walls insulated with 10mm ‘Sempatap’ internal wall insulation
  • Attic roof insulation of 100mm Kingspan, plasterboard plus 10mm ‘Sempatap’
  • Refurbished sash windows with ‘Magneglaze’ secondary glazing on all windows
  • Draft reduction through double doors to attic (& letter box!), heavy curtains,
  • New condensing boiler, replaced old 15-20 year old boiler. TRVs added.
  • Two wood burning stoves (‘Clearview Vision’ in living room heats whole house)
  • 2 x 2m2 solar panels for thermal hot water with large well insulated tank (‘AOS Solar’)
  • 8x260W Solar PV panels on South & West elevations (‘Ecodomus’)
  • Continuous running low energy fan in bathroom (‘Vent Axia – Lo Carbon’)
  • Low energy lighting throughout
  • Water saving devices include; low flow shower, low flow washers in most taps
  • Living roof from recycled carpet (‘Green Roof Options’)
  • Living wall and pond, vegetables
Benefits of work carried out:

The main benefit of the refurbishment is that now the whole house is always warm and comfortable without being too stuffy or humid. We only need the central heating during mid winter and then for all 30 mins in the morning and mid afternoon. Cutting wood for the stove is also fun. The continuous running fan and dehumidifier provide adequate ventilation and prevent condensation.

Favourite feature:

We enjoy the stoves the most including procuring, cutting, splitting and storing the wood. We burn mainly tree surgeon trimmings and waste wood to get the stove going. The main stove provides a focal point for the house and heats the whole house (including the bedrooms). A stove top fan is effective in moving the heat from around the stove to the rest of the house. We use the central heating system only for 2×30 min sessions during the coldest days. Wood storage needs to be planned well in advance with logs split and aired for at least 12 months before burning. We use a moisture meter to ensure an efficient burn.

Project update:

At the moment we have just finished the garden shed made from pallets and with a green roof using recycled wool carpets.

Have had thermal image survey of whole house (inside and out) and now addressing the cold spots.

Updated on 04/03/2014

Common questions and answers for this SuperHome

Have you had any problems using Sempatap for internal wall insulation?+

I insulated the solid walls internally using Sempatap which is only 10mm thick but quite effective.

I have fitted Sempatap in 2 houses and not had any issues. I admit I have not peeled it off to look at what may or may not be happening behind the Sempatap in areas where the seal may be less than 100%. But there is no visible damp or mould.

In terms of performance, my experience is that the rooms after the Sempatap was fitted were significantly warmer than before on a like for like basis.

This negative Telegraph Article on Sempatap does not address the following points in favour of Sempatap

1. Sempatap is a DIY product whereas the other options are not (so the cost/m2 comparison is not robust)

2. Sempatap can be fitted around coving etc which massively reduces the overall cost of internal wall insulation as the thicker systems would require replacment of coving (lots of money)

3. Sempatap is thinner and hence less obtrusive. I aim to fit more insulation on top off the Sempatap in areas where it is practical and inobtrusive.

Overall I am very happy with the Sempatap. It would be interesting to see the origin of many of the anti-Sempatap stories. My feeling is it it is a bit like 80% of objections to wind farms can be traced back to fossil fuel /nucleur lobbyists.

How did you do your underfloor insulation with sheep's wool ?+

I put the insulation between the joists in the original suspended wooden floor and kept it in place with chicken wire stappled to the underside of the joists. All this work was done from below the floor without lifting the floor boards as there is sufficient crawl space. Best to work with someone else for this as avoids climbing in and out all the time. Wool (being flexible, is good for this as the joist are not parellel (variable spacing).

Did you take up the floor boards to do the under floor insulation?+

I made a trap door through the existing floorboards to give me access. As the area under the floor is reasonably deep I did the underfloor insulation with sheeps wool by crawling underneath the floor without taking up the floor boards. Less disruption but you need to be slim and not mind confined spaces! You might also encounter some builder’s rubble en route. The underfloor can also provide good storage once cleared.

Where have you used a vapour barrier with your insulation?+

Where I have used Thermafleece for wall insulation I have also used a thick polythene vapour barrier. This needs to go on the internal face of the insulation and be 100% (be careful at edges and around sockets etc).

Wool is a hydroscopic product and so absorbs moisture without affecting its thermal properties which is not the case for other materials such as Rockwool. The wool can also be handled without a mask and gloves and is a good use of a waste product. Use dress maker scissors to cut it to size.

There are now other similar wool insulation products such as Black Mountain which you may find to be cheaper.

I did not use a vapour barrier for the underfloor insulation with Thernafleece. This has not been a problem for me.

Did you draught proof the sashes (are they original)?+

I have fixed Magneglaze secondary glazing over the sashes. I draft proofed the sashes where possible. We also refurbished the sash windows (new cords etc) and returned them to the natural wood on the internal faces. Cheaper than new windows and nicer looking.

Did you adjust the sashes for the change in size of the walls with internal wall insulation?+

I insulated the solid walls internally using Sempatap. As this is only 10mm thick I avoided having to adjust the window frames, dado rail etc. And it doesn’t matter whether you do windows or walls first.

Contact this homeowner

Assessment types

SuperHomes Assessed

A home that has been visited and assessed by us and confirmed as reaching the SuperHome standard, which demonstrates a 60% carbon saving.

Homeowner Reported

Information has been provided by the homeowner about their home and energy use prior to the installation of measures and following their installation which demonstrates a carbon saving. This information has not been verified.

Remote Assessed

The homeowner has provided information on their home including what measures have been installed which has enables an assessor working on our behalf to assess their carbon savings. This home has not been visited to verify the measures installed.


This home has not been assessed, but the homeowner has reported what measures have been installed. It may be that this home is awaiting assessment.