The green refurbishment, part four

Continuing the series of guest posts on a refurbing a Victorian house in Hackney. Joint client Bronwen Manby takes up the story, highlighting window drama, working with her brother the builder and questioning the point of party wall surveyors

So of course the ‘extreme refurb’ is over budget and behind on timetable, but

Dave the Builder, and Bronwen's brother, contemplates how to square the next circle

not drastically so – although you could also say that, by comparison to what we had in mind when we bought the house in 2007, both budget and timetable are off the scale.  To date we’ve had remarkably few crises, and, even more remarkably, everyone still seems to be speaking to each other, despite the fact that this project is so much more ambitious than we first envisaged.  There was a fair amount of tooth-sucking from my friends when I said that our builder would be my brother Dave, it being well known that working with family on a project this big can be a disaster; and even more tooth-sucking when I said that there was no chance I was going to sign a contract with him. But it’s not as if I’m likely to sue him if it did all go horribly wrong, and as Dave said, it would be strange after 30 years doing building work to sign his first contract with his sister!  The reality is that without Dave we would never have attempted this scale of work.

The main crisis since the last blog entry has been the front façade windows, where the joiners unilaterally decided to use different glazing from that specified (see box below).  So, the joiners have been harangued into re-glazing – delaying our air-tightness test until they can be completed. The frames have been left, however, so that at least the insulation on the inside of the front wall can continue to be fitted, as well as the probes that are being inserted so that insulation suppliers Knauf can monitor the effectiveness of their new product (studs made from insulation) over time in a real-life environment. After much humming and hah-ing and consultation with gurus it was decided that we did need a small ventilated air gap behind the front façade to avoid the risk of condensation accumulating on the inside of the outside wall and rotting the wooden window frames.

Worthwhile extension Meantime, the building’s new skeleton is now complete. A good moment when Mickey topped off the reconstructed v-shaped rear brickwork; and even better when the wood frame of the roof extension took shape. Some tricky problems to overcome there: to give the maximum head height whilst remaining invisible from the street, the roof of the extension slopes from the back to the front of the house – which means taking the rain from the roof through the extension to the drain pipes down the back façade.  Not an easy thing to do when there’s a chimney breast in the way, not to mention ducting for the MVHR system – and the rain water pipe can’t touch the ducting without a layer of insulation between them, or it will cause condensation in the MVHR and give us all Legionnaires’ disease or worse.  But it’s going to be worth it: the roof extension is to be my study, and it’s shaping up to be the best room in the house, with its birds’ eye view of back-to-back gardens.

We’ve also had continual re-thinks on whether we should have solar thermal or photovoltaic on the roof extension – or forget the eco-bling.  Economically they don’t make much sense, even with the grants that are available, but PV in particular does allow us to make a real saving on carbon footprint and currently it’s looking as though we’ll go that way.

While the number crunching (energy, carbon and pounds) on the gadgets has been occupying the two Roberts’ time, I’ve been sorting out the garden with Dave.  The thought of having a garden is for me almost the best thing about the new house. What’s more, we now have the most wonderful garden shed to boot, built out of re-used joists, with the old single glazed sash windows to allow for light, and some surplus sedum from the green roof of the house extension to top it. We’ll have a couple of seating areas (sunny and shaded), no lawn, and years of digging up bindweed from the rest of the plot to occupy our spare weekends.

There must be a  better system than creating a job (party wall surveyor) whose occupant is pretty much free to charge as much as he or she likes: that £7,500 would pay for the PV system.

Surveyor hell With the main building work completed, we hope that the party wall surveyors can soon check that no damage has been done to the neighbours’ walls so that the money placed in an escrow account can be returned to us.  Much as I can see the point of the party wall agreement in principle, the fact that the entire arrangement has cost us £7,500 in surveyors’ fees still rankles.  While our neighbours on both sides have been fantastically good about what must have been a nightmare of disturbance for them, their jointly appointed surveyor seems to have engaged mainly in pointless cost-escalation. There must be a  better system than creating a job whose occupant is pretty much free to charge as much as he or she likes: that £7,500 would pay for the PV system.

Once the surveyors’ final visit is over, the escrow money should then be available to apply to the purchase of our fixtures and fittings – we have been having long discussions about different types of recycled glass kitchen worktops, the environmental credentials of various types of bathroom floor covering, and how best to use the old floorboards – not easily reusable in their original role and now destined to be made into doors on the new kitchen units and cladding for the walls of my study.  We have a reused pitch pine floor to be installed, and three beautiful new staircases ready and waiting to be fitted.  Once these are in, it’ll start to look like a real house, and might even be ready in time for London Open House in September. Not a moment too soon for me either, since I sold my flat earlier in the year to pay for the works, and am camping out in an already box-filled flat of a friend who’s out of the country: an ideal solution in many ways, but inevitably I keep on needing things that are in storage.

Technical bit on windows:

The front façade windows have enjoyed much discussion, given the need both for high performance and to be in keeping with the de Beauvoir Conservation Area (much as others have not followed this rule).  The Roberts (Prewett and Cohen; architect and other half) were attracted by the idea of using the up-to-the-minute technology of vacuum glazing, which has the potential for widespread replication. But these panes come with (admittedly very small) spacers to hold the two panes apart, as well as more prominent nipples which might be too obtrusive in Georgian style sashes; and in any case the delivery time and cost were uncertain.  So it was decided to have slim double glazing with a 4mm air gap, allowing narrow glazing bars very close to the original measurements. The joiner made the sashes to fit – but then, without consulting, fitted glazing with a fat aluminium spacer bar. There are some arguments that the aluminium seal might have a longer lifespan, but they didn’t ask before changing the spec, and it was visible beyond the slim glazing bars – likely to be annoying for the next 20 years.

To hear joint client Robert Cohen discuss the challenge of this refurbishment go to the existing housing webinar run by Building magazine in May 2009

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