Modest Designs not Grand Designs

Hilary Grayson

Although I am not an avid watcher of Channel 4’s Grand Designs programme, I do dip in from time to time.  Likewise, the myriad of wonderful technical blogs out there.  Over a cup of coffee (or a glass of wine, depending on the time of day) I can dream of winning the lottery, overcoming planning objections to building in the green belt and building my own straw/lime/passiv/recycled/earthship/eco house and with gravity defying techniques.

In my heart I know it’s never going to happen.  Ok, so I don’t do the lottery (that would help) but in reality my life is complicated enough as it is without taking on a massive building project such as those featured in the programme.  They are simply too big, too ambitious, too time consuming or just too expensive.  And I cannot be alone.  I suspect that the vast majority of people who watch this programme only dream.  Like me, work, family, dogs, the need for sleep etc. get in the way!

So, if I am honest, it was more out of nosiness that I trotted along to the B & Q eco house, near Southampton recently.  I had been following its progress on the B & Q website but I think I still believed that it was going to be more of a Grand Design than a doable refurbishment.  And I could not have been more wrong. 

The first thing of note is that it is impossible to tell from the street that it is anything particularly special.  All I had was the post code.  No problem I had thought.  It will stick out like a sore thumb – these houses always do.  Well, I could not have been more mistaken.  There is not a bit of eco-bling in sight, nor is there a cubist extension thrusting skywards.  The only way I could be certain it was the house I was looking for was the open front door – they were expecting me. 

The Eco house is a pretty standard end of terraced house on the outskirts of Southampton.  B & Q paid £175,000 for what was a rather tired property in late 2010.  It had been rented out for some years and was suffering from the sort of gentle neglect common in the private rented sector.  Any family buying it would probably have given it a very similar makeover to the one that B & Q undertook, but with one difference.  While the company intended to make a home that was comfortable, aspirational for the vast majority of its customers and staff (no composting toilets!) they also wanted to incorporate as many ‘green products’ as possible and, most importantly, to make it as energy efficient as it could be.  They wanted to find out what it would take to cut greenhouse gas emissions from the typical outdated home – and indeed if it would even be possible without spending a fortune.  In other words, not so much ‘Grand Designs’ as ‘Modest Designs’.

Before going any further, there is one more correction to make.  I should not even be calling it an eco house.  B & Q refers to it as a “22nd Century House”.  This is because their research tells them that while lots of people recognise the term ‘Eco’, it is still perceived as a bit ‘alternative’ – the domain of the knitted cardigan and sandals brigade rather than the mainstream.  They also used the term 22nd Century as, before starting any work, they sat down and imagined a few scenarios that they think we will all have to face over the coming years.  It was this that dictated their approach to the refurbishment.  In a nutshell they think that, as well as government carbon emissions targets, the following will affect us all (I should emphasize that this is just their thinking – this is not policy or insider information).

  • Fuel bills will continue to rise
  • Gas usage will be restricted for homes and will be redirected to the national grid to generate electricity
  • Most of us will be living in ‘second hand’ rather than new build homes (85% of the existing houses will still be lived in in 2050)

And in addition they aimed to employ techniques that would make the house both ‘doable’ and ‘sellable’, keep the floor layout and accommodation the same, where ever possible, and, where appropriate, refer to the draft ‘Code for Sustainable Refurbishment ‘.

So what do you get?  As well as being quite unremarkable on the outside the same can be said for the inside.  You step in through the (highly insulated) front door (a new front door, but at the manufacturing process it was stuffed with insulation before the two faces were stuck together) into  a lobby and then into a smart enough but pretty unremarkable hall way - except there is no radiator.  Indeed there are only two radiators in the whole house.  One is in the kitchen and one doubles as the towel rail in the bathroom.  But I’ll come back to that.  Then you step, on rather nice but not particularly remarkable flooring, into the open plan lounge and dining room, which in turn opens onto the kitchen. 

It is only when you start looking closely that you realise that there have been a few changes.  Bounce up and down on the living room floor and you won’t - bounce that it.  The original suspended floor was removed and replaced with a solid floor because there was not enough space to install insulation under the original timber floor and leave enough air circulation space to maintain the required level of ventilation.  So a new solid floor was laid, very well insulated and incorporating under floor heating (hence no radiators).  But the kitchen already had a perfectly sound solid floor.  So rather than rip that up and install the under floor heating there, it was left in situ but again well insulated.  That is why there is a radiator in the kitchen.  But even the radiator is a bit different as it has an intelligent TRV linked to the thermostat in the living room.

The external walls are all insulated internally.  If you look closely you can spot that the bays either side of the chimney breast are not the same depth and if you look at the bay window down stairs or the windows upstairs you can see that the window cill is much wider than you might expect.  This is because the walls have 800mm of phenolic foam insulation, cunningly disguised behind a rather smart paint job (painted using either Dulux Eco paints or recycled paint from Newlife Paints and the colours are very ‘on-trend’.)

However in the hall, and indeed running under the stairs and into the kitchen, a different system was used.  The wall, which is in effect the ‘end of terrace’ wall, has a footpath running along side it, which had breached the DPC of the wall.  This was causing damp.  In addition to put 80mm of insulation on the hall wall would have made the hall too narrow.  So a different, thinner insulation product was used - evacuated aerogel which is about 10mm thick.  Evacuated aerogel panels are, according to James Walker, the project manager on the house, a bit like a thermos flask. They are foil backed panels with a vacuum inside which helps reduce heat loss.   This is why they can be thinner than other insulation materials.  It is a technology that is actually borrowed from NASA, but it does have drawbacks – specifically you cannot puncture it as it compromises its energy efficiency.  To remedy the damp and solve the insulation issue sheets of rubber were bonded to timber battens and then adhered to the wall (the idea that moisture would run down the rubber and escape via weep holes in the wall).  The timber battens on the inside provided a framework to hold the insulation and then secure the covering plasterboard.  I am inspired by the ingenuity of this solution but have lots of questions as to the longevity of it.  You cannot hang a picture in the hall! 

None of this is visible.  But when you go in the back garden you can tell where the external insulation has been fitted to the back addition.  Look closely at the bottom of the new rendering and you will see a much deeper rebate at the bottom than you would normally expect.  And look up at the beautifully ‘re-pointed’ wall by the back bedroom and you will see a most peculiar detail where the wall meets the roof over the breakfast area at the back of the kitchen. (This is where 140mm of cork insulation has been covered with brick slips – literally slivers of real brick).  And when you stand at the kitchen window you can tell that wall is much thicker than you would expect.

Upstairs the insulation continues.  But there is no underfloor heating here.  Instead the bedrooms have ‘Thermaskirt’ skirting boards.  This is a product that has been on Dragon’s Den – you can watch the highlights here .  The Dragons did not get it.  Simply you don’t need radiators – the skirting board replaces them, and works at lower temperatures hence working with the sort of system for underfloor heating. 

The windows are all well installed double glazed, and in some cases triple glazed, which, with the insulation and close attention to detail, makes the house draught free.  So another essential feature that has been retrofitted is a whole house heat recovery ventilation system.  Very discreet extract units are located in each room with the main fan unit and extract point being in the eaves in the new roof room. 

And on the very top floor is the new roof room.  This took a chunk of the budget and could be argued is a bit of a luxury, but the company wanted to make the house as aspirational and sellable as possible and the original layout had the bathroom on the ground floor.  All research told them that first floor bathrooms are more popular.  But that meant losing a bedroom. So, to keep the overall accommodation the same they put in a new roof room.  Of course, it was not just any roof room.  To make it as energy efficient as possible (and to test the concept) the whole room was constructed off site and shipped in on the back of a lorry.  Rather than describe this you can see it on the You tube clip  It all seems a bit ‘sci fi’ but I have to say that when you are in the room you would not know that it had not been constructed in the traditional way.  Also, once in the room you can really feel the energy efficiency.  It warms up very quickly and while it might seem a bit radical and high tech, I was assured that the cost of the room was actually less than had a new loft conversion been carried out in the traditional way.

And what about the heating?  I have already mentioned that only two radiators exist in the whole property.  The rest has underfloor and skirting board heating.  The heating itself does not come from gas -there is no gas in the property, despite being in an urban area it was removed.  This is because B & Q believe that private houses will, at some point in the not too distant future, be prevented from getting gas.  Gas will only be used for burning in power stations to supply electricity to the national grid.  While this might be contentious, it did mean that they could test new technologies in the refit.  They have installed an Air Source heat pump and two solar thermal panels – choosing an air source heat pump as there was not enough space for a ground source heat pump in the modest urban garden.  (Air source heat pumps – ASHP - work a bit like a fridge, but in reverse.  There is more about the technology on the Energy Savings Trust website   

Deciding on this technology solution actually created the other really sci fi feature of the house – the energy hub.  If I was being ungenerous I would call this a glorified garden shed.  Actually, that is not fair.  It’s a very expensive garden shed! 

Earlier in this article I referred to the draft Code for Sustainable Refurbishment.  This puts in a requirement for a home office and the shed, which again was factory built and insulated way beyond current building regulation standards, doubles as a home office.  The back, however, houses the ASHP and the water storage tank, while the roof supports two solar thermal panels.  The water is then pumped through a highly insulated duct buried 1 meter down in the garden, to the house, where it meets a heat exchange unit under the stairs and warms mains water to supply the hot water to the taps as well as heating the living spaces. 

The overall spend has been £80,000.  That is not cheap, but does include some changes that other people might not undertake (the room in the roof, the energy hub, a new stair case etc. – the original very steep staircase was removed only on health and safety grounds as it was known from the outset that the house would be visited by a large number of dignitaries and others).  It is believed that the changes will have cut approximately £1,200 from the annual energy bills and cut the homes carbon emissions by between 60 and 70%.

But what was most striking about the whole project was how it could be tackled piecemeal. If you are redecorating the living room it would be perfectly feasible to install internal insulation, if you are re-pointing the back, why not install external insulation first and then render it instead.  The whole house was comfortable, very warm, welcoming and, somehow, very ordinary – and that is a compliment.

What is important is that B&Q believes the market for green retrofits will boom.  It installs 35,000 kitchens and bathrooms every year — green kitouts, especially with the approach of Green Deal, could be seen as a logical extension of this. 

This is not to say it is all going to be plain sailing.  B&Q used a local builder who knew nothing about the technologies before starting and there were inevitable problems along the way: insulation panels were cut in the wrong shape, the chippy did a better job of the skirting boards than the plumber (you can tell which one the plumber did) and the main plumber walked off the job.  The project took much longer than it would have normally done and the client knew more about the technologies than the builder. 

In summary, I found the house very encouraging.  If we are to achieve the stated reductions in carbon emissions then no amount of Grand Design super projects, as commendable as they are with nearly zero emissions etc., is going to be the answer.  We need our major retailers to be providing the solutions along side new kitchens and bathrooms.  And we need solutions that are achievable.  So I say, three cheers to B & Q and let’s get channel 4 to commission a new programme - ‘Not Such Grand Designs’.  Come on Kevin – you know you want to!





Some impressive technology but £80k to save £1,200 p/a just isn't viable in the real world...& how much floor space has been lost? 800mm of internal insulation? Seriously?


£80k is the full home retrofit and refurbishment costs which included the loft conversion, removal of bathroom from downstairs to first floor, rewiring, plastering, home office, landscaping etc.

The internal wall insulation depth ranged from 10mm to 80mm with 60mm being typical so floor space lost was aprox 3%.

In terms of costs of insultion, actually brought Aerogels at market prices and not at wholesale prices this includes going down to B&Q and buying the materials on my credit card with the builder.

Hope that helps clear up those elements.



I attended the talk about the B&Q house at the Mid-summer meet in MK, and was fascinated and pretty impressed. But modest it is not! Aerogel for the floors and much of the downstairs wall if I remember rightly. I seem to remember the speaker saying that he bought the aerogel from a German supplier at a reasonable price - of course it was offered to B&Q at a reasonable price due to the potentially massive future sales. I have similar stuff (Spacetherm) on a quarter of one wall in my small cottage. It cost several thousand pounds and I could only afford it because I got it through a scheme involving a home improvemnet loan - a charge on the house. It doesn't really add up as an investment, though I think in my circumstances, along with the other work done, it will add substantial value to the house, so I'm happy. This was about a year ago and there was only one UK distributor at the time. If B&Q can sell the stuff in sufficient quantities, it should bring the price right down for the rest of us - which must be a good thing for those of us with solid walls.


Ah, should have looked more closely at the photos. Looks like the quoted insulation depths have had a zero added on. Bit more realistic.


edit: 2 insulation thicknesses corrected - thanks to Chris


The completed project only achieved 60 - 70% carbon emission reduction, which don't get me wrong is a great improvement, but it doesn't hit the target of 80% which the UK housing stock should be looking at if to achieve the Government targets of CO2 reduction by 2050....what was the SAP & EPC rating before & after I wander?
Totally agree however with this 'exemplar' project and what B&Q are trying to do. The more energy reduction measures and information become mainstream, the more home owners and builders working on home improvement projects will use, so that it becomes standard!