Webchat with Kevin McCloud

Kevin McCloudThis is an edited transcript of a live webchat with Kevin McCloud, presenter of Grand Designs and ambassador for The Great British Refab Campaign on Monday 20th June, 2011.

Kevin answered questions about Grand Designs, insulating old buildings, dealing with bats in attics, solar panels, humidity, acoustics, and biomass boilers. He also responded tactfully to marriage proposals and his status as MN crush-fodder. 

 Grand Designs |  Eco-Design and Housing | Insulation | Home design and refurb | Hab Housing | Personal


Grand Designs

Letter QOutnumbered2to1: Which is your favourite of all the Grand Design builds? (Oh dear god - I am now public banning myself it is certain I will make an arse of myself by declaring undying love and the desire to have his babies)

A Kevin: My favourite is Ben Law in the woods. Why? Because it was a film about a more sustainable way of life which mentioned the 's' word only once. And nothing went wrong. I'm a big fan of those projects where nothing goes wrong because building is hard enough anyway and always requires a degree of compromise. Problems just increase the number and degree of compromises. I'm just interested in projects that are exemplary and beautiful. 

Can I just add, there is no way that you can get pregnant from taking part in this webinar.

Letter QSoloIsAHotCougar: I have not had my loft insulated because I have no storage space as it is, so to lose the loft as well is madness. I also have passed on cavity wall insulation.  Actually Mum's house has never been colder since she had hers done. Coincidence? 

Also, I was wondering about the possibility in the future of having a third bedroom put on top of my single storey extension, but instead of a brick or block structure, I was thinking of a conservatory type of thing. Not sure if that would be environmentally friendlier than the traditional type and whether I'd end up freezing cold or boiling hot in the weather extremes. What are your thoughts?

AKevin McCloud: This is the problem I've encountered on our housing scheme in Swindon. There, we are raising the height of the ceiling joists in the loft with a second layer of timber to accommodate the deeper insulation and then boarding out on top if that. An alternative would be to sling some timbers across the trusses and board out that area. You could add 270mm of glass mineral wool (100m between the joists and then 170mm laid at a right angle to the first layer), this can be done in conjunction with laying an extruded polystyrene boards such as Space Board around the loft hatch area and then laying chipboard on top of them. Or you can look down a natural materials route, like hemp or sheep's wool. Deeper joists would give you an insulated loft space and a rigid secure platform to store your Christmas tree. But do run your idea past an engineer or surveyor to make sure you aren't overloading your roof structure. And make sure you leave room at the edges of the roof to let it breathe.

In answer to the second part of your question, that would probably only make a usable bedroom for about four months of the year. Otherwise, as you say it will be too hot in summer and too cold in winter. A single storey extension of glass like this would still have to comply with the thermal part of the Building Regulations (the law governing what and how we build), and it would likely not be possible to do that with a very heavily glazed conservatory type extension. The short answer is no I'm afraid. Build it in timber as it's the easiest way - a lightweight structure that's easy to build and which can still be super-insulated. If you want large areas of glazing, invest in triple glazed units with a low u-value (as low as 0.7 from firms like Energain) or even units made with thin plastic laminar sheets embedded into the unit (from Shardaglass). and don't forget to add external shading to the extension over large windows to reduce overheating in summer.

Letter QIklboo:  Do you deliberately pick 'eco' house builds because you know they'll go three trillion quid over budget?

AKevin McCloud:   Both our super-eco projects actually didn't go over budget - Ben's house in the woods, and Kelly and Masako's hexagonal house were built to very tight and small budgets. Of course a lot of people do go over budget because it is only human to want the very best for yourself and your family. Three trillion happens to be the cost of implementing the IPCC's (global climate body) carbon targets so it would be a bit over the top for a self-build. You are trying to wind me up aren't you?


Letter QFannyFifer: How do you manage to stay so diplomatic about it all? I liked your programme that was in India where you stayed in the slum - that was really interesting. Did you honestly stay all night in the rat house? And where did you go to the loo??


Kevin McCloud: Do you really want to know? There was a communal loo (of sorts) outside the house. Luckily and miraculously my stomach was fine the entire time I was in the slum. I did get a chest infection, however, from the pollution. As to the rats, finding them in my trousers at 2.30am was the last straw. I spent three nights sleeping in two different homes in the slum (Dharavi) by which time I'd sleep a total of about 45 minutes. It was back to the hotel after that.

As to staying diplomatic, dealing with self-builders is fairly straightforward to dealing with a film crew which demands the patience of Job.

Letter QVenitiaLanyon: Have you ever wanted to weep because of what some idiot has done to a perfectly lovely building? 

"As to staying diplomatic, dealing with self-builders is fairly straightforward to dealing with a film crew which demands the patience of Job."


Kevin McCloud: I've wept over two of them: the church in Dudley with the entombed swimming pool in the middle of it (in a bittersweet way this project saved the stained glass), and the boat on the Medway. We should never have filmed it. It should never have existed.

Letter QOOAOML:  Do you ever look at the vast expanses of glass and steel built by couples with small children and shudder at the thought of endlessly wiping off fingerprints?


Kevin McCloud: Hullo OOAOML - Yes, and at the end of a filming day, all I have to do is climb into a car and go home.

Letter QNotwavingjustironing:  Do you keep in touch with any of the "projects" you've featured on GD? There were certain people who you obviously made a connection with.


Kevin McCloud: Don't leave and put your coat down. Do you know, there aren't that many. I did sort of adopt David and Greta Iredale as my parents when I filmed the HufHaus and they rewarded me by giving me two old 1960s upholstered chairs. I keep in touch with one or two people of course. But I'm an anti-social bugger.


Eco-Design and Housing

Letter QMadhairday: Are solar panels really as eco-friendly as they are made out to be and do they save enough money from bills as to be worthwhile?


Kevin McCloud: Our Great British Refurb mantra would say "concentrate on the cheap and easy wins first". Loft insulation, draught proofing, etc, before the more expensive technologies. But, it has to be said that solar thermal heating for hot water is relatively straightforward and the payback on investment is reasonable. And thanks to the government's Feed-in-Tariff payback on photovoltaics is now possible.

A great deal has been said on the web about how PV panels never recoup their material and carbon investment but many of these rumours are based on a single flawed study from 1996. All the studies since suggest an environmental payback of between 3-7 years in use.

But to emphasise, fix the walls, floor, roof first, then look at where you get your energy from.

Letter QBinfullofmaggotsonthe45: I live in a fairly eco-friendly house in Switzerland with under-floor heating and a system that burns wood pellets and recycles the heat around the house through a venting system. Therefore, to conserve energy you keep the doors and windows closed. The problem is the humidity. At 8% it's practically non-existent! Our first winter in the house caused the family and the majority of guests to have respiratory problems. Our natural skin rugs are cracking and drying and an Indian dining table now has a large crevice running through the centre as it dried out.

It's an open plan house, so to have humidifiers running would be costly, we'd need some pretty large scale numbers of them to cover each storey, and really defies the whole energy-saving ethos.

Do you have any suggestions to improving humidity naturally, or in an energy saving (and money saving) format?


Kevin McCloud:  The traditional solution was to use miniature troughs of water suspended near or on radiators or a stove, but you don't have either. Other than cooking rice all day I can suggest a number of small strategies; a pail of water or jug near the inlet vents will help humidify the air, as will hanging out your washing indoors! You can manage your personal levels of hydration by drinking more of course, and if you have a bath leave the water in overnight and the door open. Having lived in the Alps these are all strategies I can recommend. 

Letter QEaglebird: I believe you have a biomass boiler. Can I ask what type (log/pellet/woodchip) and whether you're happy with it please? I'm about to have a pellet boiler system installed (Solarfocus Pellet Top) and am quite excited about it.
Hopefully I'll be even more excited when the government finalises the details of the RHI payments. I'd love to see more publicity about biomass systems in the popular media.


Kevin McCloud:  I'm a fan of biomass but my own boiler wasn't without its problems. Talking to other owners of larger scale installations it seems that most boilers take about six months to bed in and thereafter require more maintenance and love than your average oil boiler. My machine powers a farm and runs on chipped waste pallets which are supposed to arrive free of nails, staples and stones. Truth is the machine often spits out a horrible metal bogey and then stops.

As I understand it, smaller scale wood pellet burners are becoming more efficient and more suitable to the domestic scale. Two words of warning though: don't buy imported pellets from the Baltic because they're from trees that were downwind of the Chernobyl plume so you'd be burning nuclear fuel; and be ready for your Austrian-built machine's readout to speak perfect English up until the moment it goes wrong, when it will revert to barking German.



Letter QKittyKitty: Am I unreasonable to be slightly irritated by these government campaigns (whilst still loving yours?) They always seem to suggest we're all mad not to want to insulate our homes and make them more energy efficient, but they don't seem to take into account how incredibly expensive it can be. I'd love not to have the wind whistling through our Victorian terraced house, but I simply don't have the £2k it costs to replace each individual wooden sash window. Maybe if there were more grants available, they'd get more people signing up.

AKevin McCloud: This is very simple. The Green Deal (intended for launch Autumn 2012) is not yet even about devising the strategies for insulating our housing stock, right now it's about the funding mechanism so that homeowners do not pay anything upfront against the cost of eco refurbishing. If it works - and it could be the single most significant piece of legislation to green our homes - you will end up with a much higher performing home, a better internal air quality and cheaper energy bills. Essentially, it's a mechanism whereby your energy company or an investment company covers the cost and you invisibly repay them through your energy bill (which will still be cheaper!)

Letter QGentleOtter:   Is there such a product as paint-on insulation? And can brazenly ask for a kiss as it is my birthday on the 20th?

AKevin McCloud:  Hello GentleOtter. Many happy returns! Sort of, but not sure I'd advise them. There are products available that are marketed as 'insulated pain' however the improvement they offer in terms of heat - and money-saving when applied to an un-insulated wall - is extremely small. Generally speaking, the thicker the insulation the better, so a layer of paint isn't going to do very much. I'm sure you already have but better to think about insulating the wall itself - simple roadmap. If you have cavity walls, fill them, if not, get an expert round to look at your solid walls as you may be able to insulate them inside or out. But, and it's a big but, if you have an old building without a damp-proof course, be extremely cautious. X

Letter QSophie31: I live in a large Victorian property, but it costs a fortune to heat. I'd like to get solid wall insulation installed but I don't want to risk destroying all of the beautiful internal features.  Is there anything I can do so that they remain intact.

AKevin McCloud:  You need to be very careful – about applying any insulation to historic buildings which is not breathable and which doesn't create cavities in the wall in which condensation and mould can form. The way old buildings work can be quite complex and walls usually need to breathe. Right now there is a lot research going into how old buildings work and this will be published over the next couple of years, hopefully through the government. This is something the Great British Refurb is very keen to drive forward research on. So hang on for now. Meantime, you could consider sealing your attic trap door, secondary glazing, and draught-proofing measures; all of which can make a big difference.

Housing associations like Gentoo are experimenting with historic buildings and you could check out their websites. But I'd be cautious if you want to avoid storing up damp and mould problems. If you live in a terrace then insulating the front and back walls on your first floor, internally, is going to be less controversial than the ground floor. But whatever you do, use a breathable insulation method like mineral fibre in a stud frame. You might consider external wall insulation which can be applied to the outside face of your property's walls - either to the complete building or individual elevations – whatever is most suitable. However, do bear in mind that if the property is listed or in a conservation area you may find you are unable to make any changes to the façade.

In this instance, a hybrid system which combines both internal and external wall insulation would be worth exploring as it offers you the flexibility to adapt your approach to the project on a room by room basis. But again if you are going to go down this adventurous route do engage the services of a surveyor or conservation architect.


"Bats take precedence over human beings as residents of a building. My solution (forced on me by my ecological survey) was to build a bat loft within the roof space. It had separate entrances for different species of bat, it's lined with sarking board so they can hang and it has a heated reptile mat for long eared bats to reproduce.

Letter QGentle Otter:  How can you properly insulate a loft which is full of bats?

AKevin McCloud:  Bats take precedence over human beings as residents of a building. My solution (forced on me by my ecological survey) was to build a bat loft within the roof space. It had separate entrances for different species of bat, it's lined with sarking board so they can hang and it has a heated reptile mat for long eared bats to reproduce. The pilates room is going in next week! The bat loft has a floor covered in building paper which can be collected up once a year with the droppings and the whole structure is suspended above the ceiling of the rooms below, allowing a 300mm void which is insulated with Earthwool Ecose loft roll.

Letter QIndith:  What can you do to insulate a loft conversion? Our loft bedroom is a fairly normal loft conversion with run around storage. It is freezing, absolutely freezing in winter and of course boiling hot in summer. What can be done (cheaply!) to make it a usable space?

AKevin McCloud: If the ceiling to the roof has been finished off with plasterboard then unfortunately the only way of providing an efficient insulation solution is to take down the plasterboard, and then insulate. The roof construction itself will dictate how best to do that, maybe installing glass mineral wool between the rafters and then underling the rafters with a thermal laminate board. Or you could look at a multi-foil insulation which can fit in very small spaces. In summer, make sure you think about the ventilation you'll need - this could be as simple as opening windows on opposite sides of the building to make the air flow better. So I'm sorry but in all likelihood for a balmy year-round loft conversion you'll probably need to do some remedial work on the interiors as well.

Letter QZizo: Secondary double glazing for older properties, cheaper, flexible, far more aesthetic, no loss of original fabric, reversible, and draft proof, so why is this not being promoted instead of UPVC replacement glazing? Who are the best suppliers? Is this a gap in the low carbon/heritage market?

AKevin McCloud: I'm not promoting UPVC glazing! I'm a fan of shutters, a fan of curtains. I've built some timber shutters and some work by Max Fordham engineers has shown that they can be as energy efficient as double glazing. What I'm looking at now is how we could build shutters from double glazing itself (this is a technique that is being trialled at the HQ of the Society for the Protection of Ancient Buildings). Great.

Letter QMissMartha: Is it greener to use a so called 'green' insulation product such as sheep's wool, hemp, insulating fibre board in smaller quantities where space is limited? Or is it better to use a modern high grade insulation product? I'm thinking here of a product such as Celotex that gives you a much higher insulation value for a given thickness. People seem to shy away from products like Celotex because they seem less eco-friendly, but they are much more efficient insulators.
Are you better off saving more energy or saving less and using a more environmentally friendly product to do it?

AKevin McCloud: Well, I think it's horses for courses. I've used a combination of urethane board (like Celotex) which is a petrochemical product, together with thin multi-foil insulation in a barn roof where space was scarce. I've used breathable wood fibre board on old walls and conventional mineral fibre wool in my attic as well as sheep's wool. In my site boots I have liners made from possum fur (considered a pest in Oz).

Letter QBundlesmum:  I inherited my mother's house and have rented it out to some tenants. They complained over the winter that it's cold and expensive to heat. They are threatening to move out before next winter and they are good tenants. The house is draughty and it's really difficult to keep warm. What can I do that's not too pricey that will keep the place warm with the costs of heating lower than they are now?

AKevin McCloud:  Have you insulated the attic to a good depth (300mm is ideal)? Have you draught proofed (I spent £35 at B&Q on rubber draught proofing strip and it made a magical difference). And is your loft hatch sealed and secure? I'd also consider secondary glazing and thick curtains as more expensive options and if you have open fires put in a small efficient wood burner straight away. Also refer to the answers about the Green Deal as there will be financial help available next autumn (2012) to make larger green improvements.

Home Design and Refurb

Letter QHerHonesty:  Is it worth paying the extra for premium paints (F&B, Fired earth, Little greene) or just as good getting the colour matched and saving the money?


Kevin McCloud: You simply get what you pay for. Generally speaking the more expensive the paint the more binder and the more pigment there is in it. Meaning that it will cover more, faster and to a better finish. But don't my word for it since I'm biased, ask any decorator.

Letter QBoffinMum: For those of us doomed to living surrounded by Privet Drive style architecture in thin-walled, slightly naff houses built by greedy developers in the 1980s and 1990s, land of the pastiche Victorian door handle, the stippled pastel bathroom tile, and the fake marble kitchen worktop, what can we possibly do to improve our lot, given the current financial climate? 


Kevin McCloud: Home is what you make it. Form a community group. Tear down your privet hedges. Plant up the roundabout with wild flowers and give over half your garden to a communal space with a shared shed and vegetable plots...

Funnily enough, these are all things that my company, Hab (Happiness Architecture Beauty) is trying to weave into housing schemes that we are building. Retrofitting them into 1980s estates is maybe the next step

"Tear down your privet hedges. Plant up the roundabout with wild flowers and give over half your garden to a communal space with a shared shed and vegetable plots."


Hab Housing

Letter QRedhappy:  I'm a newly single parent on a low income, and I'm VERY excited about the houses you are building very close by me in Stroud. My question is how do I get one?! Is there a list I can join or criteria I need to fill?


Kevin McCloud: If your household income is less than £60,000 per annum you qualify to join the social housing list of your local authority. So you could put your name down through the standard allocation procedure. Alternatively, we'll also be offering homes through joint ownership and Rent to Homebuy schemes. Our website - www.haboakus.co.uk - will have details as we approach completion sometime in late 2012 (we hope to start onsite this autumn).


 Letter QDiNammic: Are you sponsored by North face?



Kevin McCloud:  If only. I have about four North Face jackets and I've had to buy every one at full price. A rival of North Face did offer me some clothing a few months ago from there summer range. What good to me is that? I need insulation.

Letter QVenetiaLanyon:  If you had to choose your own ultimate pad, would it be a) restored old house (e.g. Victorian/Georgian/older) b) barn/industrial building conversion c) brand new house of your own design? Would it have contemporary or antique furnishings, and where would it be?


Kevin McCloud:  Well Venetia, I've stopped asking myself that question. Because a bit like a window shopper, having seen so many of other people's projects I've stopped coveting them. I'll tell you what I like: a view of the sunset; an orchard (Slack Ma Girdle is my favourite variety); a glass of something and a hammock.

Letter QQuercas100: My 13 year-old son is dyslexic and very keen to become an architect. I have heard that dyslexics make good architects as they are great at spatial awareness. Is this true?


Kevin McCloud: Without wanting to generalise or sound like an expert, it depends on your son's abilities as both an artist and a mathematician. And the degree of his dyslexia. Many architects are indeed dyslexic but I suspect that their abilities as architects are influenced by many factors. Good luck to him though.

Letter QSpirael: I can't believe no-one has asked this yet... What's your favourite biscuit, Kevin?


Kevin McCloud:   I've been waiting for this. My favourite biscuit is... A plain chocolate digestive with half a banana sliced on top of it. It's the unrivalled combination of potassium, chocolate and sugar that gives me that hit.

Letter QGetorf: Do you realise Kevin that you are crush-fodder for an alarming number of women?


Kevin McCloud:  That makes me sound like I'm about to put in a giant mill and dispersed like chicken feed.

Letter QFimbo: Do you style yourself? At this point do I admit buying my husband a North Face parka because of yours?


 Kevin McCloud: I'm very proud that I'm responsible for all my own sartorial decisions. Even though most of the directors, producers, researchers and tea-boys I work with all keep pleading me to go shopping and allow them to choose for me.


Last updated: 9 months ago