July 2008

After I blogged about the various codes, guidelines and schemes I’ve seen mentioned in magazines, and admitted my confusion, I received an email from Martin Lawless of MTT/Sustain, an energy and sustainability consultancy. Martin kindly explained the relationship between the Code for Sustainable Homes, BRE’s EcoHomes, and BREEAM. He has generously given permission for me to blog it, as he explains things with more clarity than I could manage!

The Code for Sustainable Homes, ‘The Code’ or ‘CSH’, was launched in April 2007, superseding the environmental assessment method EcoHomes. It introduces a single national standard to be used in the design and construction of new homes in England, based on the BRE’s EcoHomes scheme, but with more challenging targets. From May 2008 a CSH rating is mandatory for all new homes built in England.

The Code sets out six increasingly demanding levels for the environmental performance of new homes, with minimum standards for energy and water use, surface water management, site waste management, household waste management and the use of materials.

Each level sets stringent standards, particularly with regard to energy (measured with respect to dwelling carbon dioxide (CO2) emissions) and water consumption.

The Code is initially voluntary, with the exception of registered social landlords, who currently have to build to a minimum of Code Level 3. For all granted-funded homes the minimum standard of CSH compliance to be three years in advance of the national standard is required. At present all properties are being designed and built to level 3 standard with the target of zero carbon set for 2013.

Adoption of the Code is intended to encourage continuous improvement in sustainable home building. Performance targets are proposed which are in excess of the minimum needed to satisfy Building Regulations; but are generally considered to be sound best practice, technically feasible, and within the capability of the building industry to provide.

There are three approaches to encourage performance in these categories within the code:

1. Minimum standards at each Level - energy efficiency of the property and water consumption

2. Minimum standards for Code compliance at any Level - materials, surface water run-off and waste

3. No minimum standards - pollution, health & well being, management and ecology

Mandatory Post Construction Reviews (PCRs) dictate that what is built should be as what was proposed and so meticulous document management is essential during construction.

The Code for Sustainable Homes is administered by the Building Research Establishment (BRE), but the scheme technically belongs to the Department for Communities and Local Government.

BREEAM (the Building Research Establishment Environmental Assessment Method) has been around for a number of years and has a variety of forms for differing building types (offices/industrial/retail/prisons etc).

The BREEAM Office at BRE created and continues to run the Code for Sustainable Homes predecessor EcoHomes (which now only really applies to dwelling refurbishments and to dwellings not in England).

Kev and I like to go to the local gym as often as we are able, usually two or three mornings during the week, with longer sessions on the weekend if we can. I never used to be a gym person nor, indeed, did I used to have any truck at all with physical exercise. But three years of contentment has put the pounds on, and I am determined to get them back off again.

So I can’t imagine building a house, now, without having room for some gym equipment. It doesn’t need to be much, just enough to keep us moving. Kev swears that the best thing for a compact home gym is a Nordic skiing machine, because apparently it’s good for exercising your whole body.

Me, I want a simple treadmill. And I feel that it’s important to say that my reasons for wanting one have nothing to do with these, honest:

If there’s one thing that drives me potty, it’s seeing a house described as “eco-friendly” just because it has really good insulation. The latest offender is an article in Build It’s August issue, (page 54 if you’re curious), which says “because of its high insulation values, [this house is] eco-friendly to boot.”

Reading on, we find out that the house is made using an insulated concrete formwork, i.e. they stack up hollow polystyrene blocks like giant lego and pour concrete into them. So that’s polystyrene, which is made from petrochemicals, and concrete, which produces some 5 - 8% of the entire world’s CO2 emissions. Neither material is particularly environmentally responsible or sustainable.

Although the owners have underfloor heating, they don’t use it, relying on an Aga and heated towel rails instead. One of the owners is quoted as saying “We keep it as a steady 75 degrees [24C] and the Velux windows in the [upstairs] kitchen area are left open all year to prevent it getting too warm.”

Agas are not known for their environmental credentials, specially as most of them run on fuels such as oil, and if the house is so hot that the windows need to be kept open to regulate the heat, that’s a big waste of energy.

We are later told “The eco-element of the house extends to the wall finishes - every wall has five coats of beeswax, applied directly onto chemical-free plaster with a sponge.” But I’m not sure how the use of beeswax balances out the use of all that concrete and polystyrene.

I guess there’s two ways to look at this: either the house includes a lot more environmentally sound materials and practices than the article tells us about, or it’s not actually eco-friendly at all. It may be really well insulated, but can’t be our only marker of sustainability. Indeed, as it’s presented, I find it hard to understand why this house is being labelled as eco-friendly.

I haven’t even begun to wrap my head around the various code, guidelines and schemes that have sprung up around environmentally sustainable building over the last five or so years. So far, the ones I’ve seen mentioned are:

Code for Sustainable Homes
It’s been mandatory since May for all new builds to be rated using the Code for Sustainable Homes, that’s if you can figure out what it is. Homes are given a star rating, between 1 and 6, where 1 star is the basic rating and 6 star is the best. It measures pretty much everything, from energy and Co2 emissions to waste, pollution and materials.

Standard Assessment Procedure
Rates the energy performance of dwellings, measuring energy costs for lighting and space/water heating.

Leadership in Energy and Environmental Design
A ‘Green Building Rating System‘, developed by the U.S. Green Building Council (USGBC), which rates the design, construction and operation of buildings. It focuses on “performance in five key areas of human and environmental health: sustainable site development, water savings, energy efficiency, materials selection and indoor environmental quality.”

BREEAM Rating System
Another UK scheme from the Building Research Establishment (BRE) which seems to be a lot like the Code for Sustainable Homes, but I can’t immediately see from the website if two are actually the same thing or different.

Passivhaus
A voluntary German standard for energy usage, Passivehaus is also promoted in the US.

It’s going to take more than a little willpower to start reading through the details for all of the these schemes and, given that I am so far away from builging, I wonder if there’s any point. By the time Kevin and I break ground, it will all have changed anyway.

I note from the ISite blog that the UK Green Building Council “has promised an open source sustainability code, to help address the confusion arising from the myriad of different green building standards with a new Code for Sustainable Buildings, joining in the debate / tussle between LEED and BREEAM.”

The UK-GBC say:

UK-GBC Chairman Peter Rogers added, “The UK-GBC wants to see very wide take-up of robust and customer-friendly tools, and we believe that the standards at the heart of a new Code for Sustainable Buildings should be ‘open source’, meaning that such a Code could potentially be incorporated into a range of different tools, from a range of providers who could then compete in terms of service provision, without confusing the industry with different standards.”

And ISite suggests that they adopt a Creative Commons licence, which I think is a great idea. I just hope that they make it much simpler for novices to understand, and ensure that third parties can use the information to provide tools to help people actually implement the code.

Because all the green building codes, guidelines and schemes in the world are worthless if no one understands or implements them.

I was browsing through the Way of Cats blog when I came across their review of Litter Robot II - an automated litter tray which self-cleans and provides always-fresh litter for the kitties. Clean litter is deeply important to most cats, and they’ll refuse to use a litter tray if it doesn’t come up to snuff.

Anyway, I did a bit of digging (no pun intended), and it seems that many automated litter trays require that you buy either special silica gel crystal littler, or litter that comes in a special cartridge that fits in the bottom of the unit, which seems expensive and wasteful to me. ScoopFree, for example, requires you to change a tray cartridge of crystal litter every 30 days (although users report that you have to change it more often, for some, every five days) and many reviewers on Amazon report that the tray begins to stink pretty quickly.

The Litter Maid is another rake-based system which, like the ScoopFree, drags a rake through the litter to gather the poo at one end of the tray and conceal it. Unlike the ScoopFree, the Litter Maid uses clumping litter, not crystals, but it does require a special ‘waste receptacle’ which you have to continue buying for the lifetime of the litter tray. According to reviews, the rake-based systems tend to have problems getting jammed, which doesn’t sound so great.

Then there’s the CatGenie, a litter tray that uses washable litter and which actually acts more like a toilet, with the solids being liquidised so that they can be flushed away into your mains waste outlet, and the liquids being rinsed out of the litter and, again, flushed away. The entire system is cleaned using a special ‘SaniSolution’, which, of course, you have to keep buying (it’s their version of the waste receptacle/tray cartridge, I guess).

Now whilst it sounds like a good idea, the reviews on Amazon tell a different story. The system can get clogged up with poo and hair which requires manual unclogging. (Mmm! Poo soup!) It can overflow - remember that you’re pumping water into this thing - and at least one review that I read was from someone who’d had her house seriously flooded. Others have actually had to get plumbers in to hook the thing up to the mains. (It’s well worth reading this review, if only for the laugh.)

So this brings me to the Litter Robot, which has an entirely different design. Rather than having a rake or a flushing mechanism, the Litter Robot is a globe that does a sort of rotating sifting thing… you know, this video explains it better than I can describe it:

The main problems, from the negative reviews on Amazon, seem to be either that the cat doesn’t want to use it, or that there are mechanical issues. There are also issues with big cats ‘overshooting’, and ending up standing with their back to the door and pooping on the step instead of in the litter. One the plus points, you don’t need special poo receptacles so you can use normal bin bags, and any decent clumping litter will do, so it’s cheaper to run.

But all of these automated solutions have problems, and none of them are cheap. but if the customer reviews are anything to go by, then the Litter Robot comes out ahead, with far fewer bad reviews than good. Indeed, if you count 5 and 4 star reviews as good, and 3, 2, and 1 star reviews as bad, it pans out like this:

• Litter Robot - 85% good, 15% bad (196 reviews)
• Scoop Free - 76% good, 24% bad (128 reviews)
• Cat Genie - 68% good, 32% bad (309 reviews)
• Litter Maid - 52% good, 48% bad (491 reviews)

Whilst it might seem like an extravagance to have an automated litter tray, for an indoor cat it could be really useful to ensure that they always have a clean place to go. And any reduction in contact between humans and cat faeces also reduces your chances of catching toxoplasmosis.

It’s going to be a while before Kev and I get to have cats, so by the time we are ready for our Litter Robot I hope many of the problems will have been ironed out.

When I was at Grand Designs Live, I was taken with the GLASSeco work surfaces installed in the Log House.

I was really impressed by the depth and luminosity of the material, specially when it was lit from underneath. Having finally had a chance to look into it a bit more, I’m even more impressed with its green credentials.

GLASSeco surfaces are made of 95% recycled materials, including local waste glass, which would otherwise have gone to landfill and which they source themselves from the hospitality trade. The glass is sorted by colour, cleaned, smashed into chips, and set in a solvent-free resin which is poured into a bespoke mould. They can include all sorts of other recycled materials in with the glass chips too, including crushed oyster, clam and other seashells, or aluminium filings.

GLASSeco is available in a number of colours - I particularly like the ones with big chunks of green glass in them - and matt or polished finish. It can be made into work tops, tiles, floors, steps, or stones; can be used inside or outside, or even in a wet room or shower; and can even be made into tables.

This video from GLASSeco explains more about the manufacturing process, and also explains about their factory’s green credentials:

Prices for a GLASSeco work surface start at £270 per linear meter, but each one is bespoke and unique.

This definitely goes on the list of things I’d rather like in my house!

One of the big problems with indoors cats is that they frequently prefer to be outdoors cats and keeping them in when they want to be out can be, well, a bit tricky. As anyone who has attempted to keep a cat in can attest, they are very good at slipping unnoticed between legs, jumping out through windows you didn’t think they could reach, or squeezing through gaps you could have sworn were too small.

When my parents got Castor and Pollux, they attempted to kitten-proof the garden so that they couldn’t roam. That worked well whilst they were little, but eventually they figured out how to get around the strategically positioned chicken wire. No matter how hard my dad tried to find and plug the holes, they would find a way through.

Cassie, in particular, has a love of roofs and will leap from roof to roof, all the way down the road.

All three cats, Cassie, Polly and Fflwff, also have a fascination bordering on the obsessive with the front door. Given the opportunity, they will make a run for it, hiding out under the car or disappearing off into next-door’s garden before you can blink. Indeed, I think they believe the front door to be the gateway to Shangri La, so keen are they to get through it.

If my parents had a porch, however, they could use it a bit like an airlock, closing the inner door before opening the outer. That would prevent the usual cat location and head count ritual prior to each leaving of the house, and would make accepting deliveries and guests a much simpler process.

(If my parents sound a bit obsessive themselves, I can forgive them. They’ve had so many cats die in car accidents they are very protective, although they are easing up a bit now that they’ve realised that not only do they live in a much safer neighbourhood now, but also that the kittens can out manoeuvre them nine times out of ten.)

If you’re really serious about keeping your cat inside, though, a utility or mud room can fulfil the same function for the back door, allowing you to ensure that kitty never gets anywhere near slipping past you. I like the idea of a mud room - a place to take off muddy shoes, hang up wet coats and dry umbrellas. Kev’s very keen on the outdoors, so one day, a mud room is going to be essential.

But what about windows and patio doors? In the US, they use screens to keep out flying insects, but they can also keep in recalcitrant moggies intent on experiencing the great outdoors. I’m not overly keen on the look of screens, however. They do rather ruin the view, so if we move over there I’ll have to find some recessed screens that I can hide away in the wall when they are not being used.

It may sound a bit over the top, but if we are going to be serious about having happy and healthy indoors cats, then we need to plan for these everyday realities. And it’s far easier to include a porch, mud room and screens in the original design than it is to add them later when you realise how useful they’d be.

Whenever I travel, I always try to make sure there’s time to pop into a newsagent before I get on the plane, train or coach. For some reason, travel interchange newsagents normally carry a good selection of self-build magazines, so I can usually pick up some light reading for the journey. Last week, Kevin and I went to Prague for a conference - a great opportunity to read August’s issue of Homebuilding & Renovating.

Together we leafed through, point out things we liked and things we found hideous to each other. Eventually, we reached page 42 and the beautiful Border Oak house that Stephen and Elizabeth Roberts built in Pembridge, Herefordshire, which is “well known for its heavily timbered mediaeval ‘black and white’ houses”.

I think you’ll agree that it’s a beautiful house, quintessentially English, and full of character.

The Roberts said that they saw an article in H&R about a Border Oak house and immediately wanted one. They ordered a three bedroom cottage, with “brick and block ground floor, an oak framed first floor and reclaimed clay roof tiles which give the building an authentic aged appearance.” It’s one-and-a-half storeys high, with dormer windows, which give sloping ceilings in the bedrooms.

H&R says:

Laying underfloor heating throughout the building avoided the need for awkward radiators, which Elizabeth and Stephen felt would spoil the authenticity of the interiors, and also greatly pleased the couple’s pet tortoise, Darwin, who adores the warm floors.

I can imagine that underfloor heating, which I definitely want, will please our FutureMoggies too!

The ground floor has flagstones and the first floor has oak floorboards. They have a brick inglenook fireplace in the lounge, with an oak lintel, woodburning stove, and flagstone hearth. The kitchen is gorgeous, with oiled hardword work surfaces and all modern appliances hidden from view.

I have to say that Kevin and I both love this style of house - it’s so warm, friendly and inviting. If we end up building in a British village, then I will definitely look at this as an option. I expressed concern to Kev that if we move to the US, this wouldn’t exactly fit the local vernacular, to which he replied that the nice thing about the US is that you can ignore the local vernacular and do whatever the hell you like!

And if you want a bit of oak-frame porn, you can do no better than visiting the Border Oak website - click on ‘portfolio’ and knock yourself out. There are some beautiful houses there to really get the juices flowing.

Ah, one day.

I’m very keen on the idea of building a oak-framed house, preferably one with lots of big windows and the posts and beams exposed. Oak is beautiful, sustainable, and strong, but the question I’ve been struggling with is, what do we use to fill in the gaps between the oak posts and beams?

Cob is, of course, an option, but if we end up with a plot that doesn’t have the right sort of subsoil, or not enough subsoil, to work into cob then we’d have to bring some in, which would leave a big hole somewhere. Cob is also very labour-intensive, and cob walls end up very thick - 450 - 600 mm thick, according to the Devon Earthbuilding FAQ. I really don’t want the walls of my house to drown out the oak frame and I worry that perhaps cob might do that (but I’d welcome any cob experts who want to weigh in on that point). It also takes quite while to dry out, which slows the build down.

Straw bales are another good, eco-friendly option, but they suffer from the same wall thickness issue as cob. Straw bale walls tend to be about 450 - 500 mm thick, which is similar to cob and again, seems to my novice eye to be a bit thick.

In July’s Self Build & Design, I discovered what might be the answer - hemp and lime (HL). Unlike cob and straw, HL isn’t a load-bearing material, but if we’re using a timber frame, then we don’t need the infill to be load bearing. Hemp and lime is a good insulator, requiring no additional insulation and no cavity, and it’s environmentally friendly - sequestering away over 110 kg of CO2 per m3 of wall covered. It also allows for much thinner walls of just 300 mm, and can be clad in anything from render to timber to masonry. Like cob, HL gives you lots of thermal mass, i.e. it warms up in the sunshine and releases that heat when the house cools, a sort of passive solar heating.

In terms of construction, whilst you can go the complicated way and spray the stuff on, you can more easily build HL walls by using shuttering, i.e. put up sheets of plywood and pour the mixture into the gap. According to Self Build & Design, it’s not the cheapest material at about £68/m2, but then you do save money because you don’t need to buy additional insulation.

Like many ‘alternative’ building materials, there are issues getting planning and building control officers to accept it, as many of them are not up to date with unusual building materials. But Hemcrete, produced by Tradical, have been through all the tests and can produce the relevant certificates.

Obviously I still have a lot to learn about building materials, but I’m really rather attracted to HL. If you have opinions on cob, straw and HL, do leave a comment!