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1960’S Standard Semi


In September 2004 our family comprising the author Mark (38), my wife Steph (33) and son (5) downsized from a brand new four bedroom detached house to a 1965 semi detached house. The semi was nothing special architecturally and was similar to countless thousands of others around the country. The one advantage was it had the potential to enable us to extend and alter the building to suit our own requirements.

The house was located on a corner plot with a nice wedge of garden that was ideal for extending and was purchased for the asking price before it was fully advertised. The house consisted of living/dining and kitchen on the ground floor and 3 bedrooms and a bathroom on the first floor with single storey garage attached on the side. Originally built with a local mains feed oil-fired hot air heating system, in the 1980’s the heating in the house was replaced with storage heaters and hot water immersion. This part of the village had no gas and the original oil system was all but redundant.
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Once in and sorted, the first thing was to improve the insulation of the existing. The existing cavity wall was injected with blown Rockwool. As we were a semi with storage heaters this cost us all of £50 – the government paid for the rest! They could have undertaken works to the attic for another £50 but wanted to do this ourselves.  Not only did this allow us to build an attic storage area above the 270mm of insulation, but also construct baffles at the eaves to ensure a clear ventilation route.

We also replaced the existing uninsulated timber hatch with a new insulated plastic example that was larger, draught proofed and fitted with a hinged door. It was a visible improvement on the old one.

The next plan was to add to the existing building, a two storey well-insulated extension was to provide for a large kitchen/dining/family room and allow for the conversion of  the old kitchen to a utility and downstairs WC. The first floor would provide a master bedroom and en suite. An additional room was added into the roof to provide a ‘den’ for our son. The extension became a priority as child number 2 was expected. Finally a new garage and drive was completed to the side of the site.

Planning permission was granted with very few conditions and Building Regulations was achieved with few queries. (Working in an Architectural Practice as an Architectural Technologist and Sustainable Design Manager) – I hope I would be able to achieve this without too many problems.

BEFORE                                                                                   AFTER


A contractor/project manager was brought in construct the shell of the extension, new garage and drive. (Stuart McDowall Ltd – Faringdon 01367 240377). This went extremely well with Stuart arriving on site most mornings. The only thing I had to pick up on was the fitting of the Rockwool wallbatts; these were not butted together as tightly as I wanted. I did not want any gaps/cold bridges from missing insulation. Once the shell was complete it was made weather tight with new double glazed windows. It was then time to crack on with the internals and fitting the roof and floor insulation, screeding, floorboards, stud partitions and plasterboard. Our daughter had also arrived so the new space was soon to be required.

The garage was originally going to be rendered at a cost of £700. We decided to add horizontal battens to the blockwork and face it with brush matting at a tenth of the price and better for wildlife. Also believe it also looks better that stark render.

The ground floor of the kitchen/dining/utility/wc were completed with 100mm of Kingspan insulation below sand cement screed (U value – 0.17W/m2K). (2006 requirement 0.22W/m2K).  The lower the better for these U values.
The walls were standard brick exterior leaf (one area was block and render) with 100mm of Rockwool cavity insulation and Thermalite Aircrete blocks internally. (U value – 0.26W/m2K) (2006 requirement 0.3W/m2K)
The roof had 100mm Kingspan between rafters (tightly fitted!) with 70mm Kingspan insulation below with a plasterboard finish. This insulated roof line instead of ceiling line then provide the attic den. (Roof U value – 0.16W/m2K). (2006 requirement 0.2W/m2K)
Windows to the existing house had been replaced when we purchased the building with uPVC double glazed/low e argon filled windows. Generally I do not like uPVC but on the 60’s house it was something I could live with. (U value – 1.5W/m2K). (2006 requirement 1.8W/m2K).

We brought all of the Kingspan insulation from a company in Wales that supplied seconds. I cannot recall the savings but I believe they were a third of the price from a merchant and it was also delivered to the door. (

The original cylinder seemed to be same age as the oil fired heating system. It only had an insulation blanket and leaked heat rapidly. This was replaced with a new twin coil highly insulated cylinder allowing for the connection of two heat sources. Up to this point all of our water had been heated by electric immersion - not very cost effective or green.

The first heating source we fitted was a Worcester Bosch twin flat panel solar hot water system. ( (This was fitted by Solar Solutions Direct in Eynsham – ( with the advantage of £400 back from the government as a Low Carbon grant and £300 from Worcester Bosch who were running a promotion. The panel installation cost £2700 though with £700 cash back, the £2000 cost this was a good investment and in replacing an electric immersion and price increase the payback will be quite rapid. This was connected to the lower cylinder coil and was fitted and running in two days. (Worcester were still running the promotion – August 2008).

The solar panels were fitted on the rear South West roof and no planning permission was required. The advantage of this orientation with a young family was that all the hot water would be provided in the afternoon and evening when required the most.

In relying on the sun, you learn to work around the weather. On sunny days when we then have abundant hot water (the system turns off when the water sensor at the bottom of the cylinder reaches 55 degrees or the panels themselves reach 131 degrees) we do standard washing at 40 degrees and sheets/towels at 60 degrees. Additionally, the kids have their bath/shower early and we still have enough water late at night for 2 more showers or a bath. Even though we have a shower pump it runs at only 9 litres a minute and as enjoyable as it is we do limit the time we spend in there.

The solar panels were installed in September 2007 and so far the only period that the sun did not provide sufficient hot water was December 2007 / January 2008. During this time and a few periods in February / March the water was heated by the second heat source. Even when we have 1 or 2 overcast days the cylinder is so well insulated it is still hot for those days when the sun is not shining. So far (up to September 08) the immersion has not been used once.

‘Whirligig’ (rotary dryer) in the garden or two clothes horses which move between the utility and garden depending on the weather.

The second heating source was a stove. We decided to purchase a Stovax Stockton 6 wood burning / multi-fuel stove with water heater. We brought this from  ( for about £550.

Luckily the chimney had not been removed as sometimes happens with older properties. When the fireplace was opened up the original hot water flow and return pipe work was in place and could therefore be reused. These pipes were connected to the stove and the upper coil of the new cylinder. Though missing, the ‘heat sink’ radiator in the bathroom was replaced with a second hand radiator brought on eBay and fitted without thermostatic valves. As the stove is an uncontrollable heat source excess heat is dissipated through this radiator.

The final part of the system was a smaller header tank in the roof space supplying water to the stove fed hot water circuit. When the stove is on, it gradually warms up the cylinder and also provides a lovely warm bathroom that can actually feel too warm!

When we have the stove working the water gradually heats up and rises. In fact it is more the cold-water sinking that provides the circulation. This acts in the same way as the solar hot water system by transferring heat but without an electric pump. The cost of the large bore pipe work, header tank and chimney liner and twin wall flue came to about £1000.

Another advantage of the central ‘fireplace’ stack was that it was built with a 3500mm high, 800mm by 750mm masonry core, capped with a concrete top on which the cylinder sat. Originally this open core was completed with louvered openings to all rooms on the ground and first floor for warm air circulation provided by the oil heater. We decided to re-open two ventilation grills, which served the original bed 1 and bed 2 (now the children’s bedrooms.) Same principles as before applies, hot air from the stove rises through convection and enters the bedrooms. For safety, carbon monoxide detectors have been fitted in the living room and these bedrooms.

Although the living room, kitchen/dining, children’s bedrooms and landing have storage heaters – they are very rarely on. The master bedroom, en suite, office/bed4, utility and cloakroom have no separate heating and has never been required. Even with no heating, the window in the master bedroom is open at night all year round.

In 2007 before we started all of the low energy alterations – we used 4120kWh Standard and 7850kWh Economy 7 for heating, lighting, hot water & cooking.

Now all of the light fittings, whether pendant, mini candle, fluorescent or recessed spots are fitted with low energy bulbs. Nearly all electrical items are turned off fully or at the wall – try not to use standby. Even the broadband wireless router is on a 24 hour timer so this is off for 6 hours a night. Satellite is turned off at wall when not in use – as this biggest user of power even on standby.

As the house came with Standard and Economy 7 it was decided to use this low cost electricity to our benefit. Consequentially the dishwasher is on a 3 hour timer and runs after midnight. Also if there is limited hot water the washing machine is also goes on late at night so as to run on the Economy 7 electricity.

It has been noted that for the last six months  (April – September 2008) our electricity usage came to 1163kWh of Standard and 301kWh of Economy 7. Based on 13p per kWh Standard and 5p E7 this roughly equates to (£151 and £15). So £166 (excluding VAT/standing charge) for the last half year - less than £1 a day, which is not bad!

We have yet to do a full year cycle with solar and stove. The solar and other changes mentioned before is giving us a saving of 33% on the standard electricity compared to last year (at least for half year). Economy 7 cannot be assessed yet until a full winter without the use of storage heaters is completed. It is hoped we can run the house on a max of 2500kWh Standard rate and 900kWh E7 rate with storage heaters on a few times over the winter. (Therefore we are looking to run the house on £350 + standing charges).

A rated Bosch fridge freezer and A rated Bosch Washing machine.
Washing - We also wash with Indian soap nuts for normal coloured washing and standard eco detergent for whites.
Cooking – As we have no gas the cooker is a large twin oven electric (B/C rated). We use the small oven where possible otherwise standard cooking though using microwave where possible for vegetables etc.
Eco kettle is also a good little invention – boiling only the amount of water you require.

In revamping the bathroom and installing the new en suite it was decided to try and ‘save’ some of the water from the bath and shower. A separate drainage drop was formed and connected with an isolator valve in the SVP boxing in the Utility. During the winter this water goes into the mains drain but during the summer (in periods of draught!) the water can be switched to go into two 210 litre rainwater butts. These two water butts collect both rainwater and grey water so can store either. We have two other 210 litre water butts collecting just rainwater and have yet to run out.

The bathroom suite was new when we purchased the property but we retrofitted the WC with a 4/6 litre flush. The new en suite and cloakroom WC’s were both fitted with the same as standard. Taps are low flow and also aerated types were possible and are not left running. Even the kids are well educated and do this themselves.

In 2007 the family used 96 cubic meters of water (96000 litres). This equates to 263 litres a day or 66 litres per person per day. For a 3 Bed House/4 person household this is a very low water usage. (The BREEAM Code for Sustainable Homes standard – the highest rating Code Level 5/6 has a requirement of max 80 l/p/day) – don’t ask me how we are lower than this – we do have showers and baths but use the rainwater for the garden and car washing. We currently pay a standard water charge of £15 month that covers it.

Ground floor kitchen/dining completed in black tiles – always warm with 100mm insulation under foot. Black tiles also absorb heat from the sun during the day and release it at night. Walls/ceilings are just plastered and emulsion painted.

In the garden we have the compost bin that seems to be more of a wormery! The amount of worms removed every time we take out compost is amazing. The compost is used to feed the fruit trees and other fruit bushes. This works well with all the items we can compost.

We also have a ‘Bokashi’ bin that sits in the utility and is where we put cooked food and also other scraps we do not put in the compost bin. The drain off can be used as a organic feed or drain cleaner! Once full and it has stood for a few weeks the waste can then be dug in or added to the compost bin. (

Private enclosed breakfast area to the East.
Summer seating BBQ area to South West. Clay Chimenea external wood burning heating stove on terrace. LPG heaters should be banned!
Fruit Trees – pear, cooking apple, plumb and eating apple.
Fruit Bushes – blackberry, raspberry and strawberry.
Bat boxes, nesting boxes and insect houses.
Front garden – section of wild garden area often covered in bees and butterflies.

About one black bin bag of rubbish a month though no benefit from council tax reduction. We recycle all plastic and cardboard to local tip on way to work and other plastics at the local leisure centre. Kerbside collections pick up plastic bottles/glass/paper/metal.

Seal all electrical/pipe holes through the FF ceiling with expanded foam.
Possibly double doors to form draft lobby in hallway. Doors removable for summer.
Secondary heavy curtains for the winter. Removable for summer.
Look at the cost of PV panels – one day if we have some spare money. If the government changes the policy to match Scotland /Northern Ireland, who currently have 50% grants whereas the current English/Welsh system currently has, grants upto a maximum of £2500. (Changed in 2007 from 50% due to possible overload of the useless domestic wind turbine applications).
Doubt much else we can do with this existing house.

Tumble dryer – fills a space in the utility! – For emergencies only and then only to finish off air dried clothes that have been drying overnight!
Storage Heaters. Retained - if ever we have a cold winter again – we can use these – really only applies to the kids rooms.

With this all completed we now have our ideal house.
On the ground floor we have a large kitchen/dining. The kitchen leads to the utility and cloakroom. We have a main living room and a reading/kids living room. The kitchen/dining room leads onto a private outside breakfast area that is east facing. The living room opens onto a south-west facing terrace, ideal for sitting out in the summer.
Upstairs we have three double bedrooms; the master bedroom has an en suite. There is a family bathroom and also a home office. There is also an attic playroom over the master bedroom. Could not really ask for much more.


Design and build a new house – green and sustainable. To live with low energy, solar hot water, PV/wind turbine power. Borehole for drinking water, rainwater for WC/washing. Reed bed for sewage. Not relying on any external suppliers. Stand alone living with chickens and large vegetable garden. (What were my lottery numbers!)

© Climate Outreach Information Network, 2006-2007
Design - AHG