Durable doors

 I'd like to share an experiment in joinery detailing to keep maintenance to a minimum.

 Last summer's porch reconstruction just needed some doors to complete the work. 

There are three identical doors - two on the left to make a double door entrance, and a single one on the right leading to the woodstore. They're 2.35m high and 560mm wide.

The concept is a frame, rebated to take the glass, with a full width cover piece to the sides and top, and an aluminium 'sill' below. This drains the water away from the ventilated cladding to the lower part of the door. The 4mm toughened glass is dry glazed with a neoprene foam strip, squeezed in place.













The frame and cover pieces are made of  lengths of 120x27mm American Yellow Pine, beautifully straight-grained, hard and resinous. I cut the rebates and half lap joints on my radial arm saw, and glued up with exterior PVA without fixings. The inner frame is finished in Danish Oil and the cover pieces are left untreated. They are fixed with M6 stainless steel countersunk set screws, tapped into 5mm diameter holes. The lower cladding is untreated Douglas Fir, fixed to shallow battens over a breather membrane to created a rain screen cladding. Hinges are parliament hinges to get a solid fixing into the main frame. Handles are rescued samples.

I've waited a few months to see if moisture movement would be a problem with winding and binding but all seems surprisingly stable.  Goodbye putty and paint!

Steps towards more sustainable specification

Last Thursday we hosted our spring sustainability talk. Graham Hilton, Gary Newman, and Brian Murphy of the Alliance for Sustainable Building Products (ASBP) gave the assembled crowd an engaging and fast paced presentation of the difficulties in specifying environmentally sound products.

As energy use in buildings falls (due to improved efficiencies of mechanical and electrical systems) the embodied energy of building materials becomes a more significant proportion of its carbon footprint. Part of the aim of the recently established ASBP is to tackle this issue and demystify what is a “green” product. Any visitor to Ecobuild will be aware that the vast majority of suppliers claim to be conscious of the impacts of their products. While many are likely to match their claims there is no standardised method of providing hard evidence. If a system such as Natureplus was in place, specifiers could consider this figure along with cost and aesthetics when choosing which brick, plasterboard, etc. to pick. Brian painted an image of manufactures fiercely competing to win gold in their product category.

There was interesting question and answer session afterwards, most memorable was the debate regarding the BRE’s Green Guide to Specification. It’s author Jane Anderson discussed it’s strengths and weakness, along with ways in which the ASBP’s work can address it’s shortcomings. Our guests left with an awareness of the urgent need for clarity in this critical carbon cutting area of construction.

Here at Cullinans we will be enthusiastically following the developments of the ASBP in the future.

Arts and Crafts modern

Traditional natural building materials such as timber, cob, thatch had to be used in a way that recognised their limited durability. Steep roof pitches, generous overhangs result. If these rules were not followed they would have fallen apart quickly. Well detailed, they age gracefully and delight with their marks of age.

Fed up with constant repairs - in particular reputtying and painting timber windows at the beach shack - has made me think about how to detail contemporary building in a traditional way.

The existing porch was detailed to invite water into it, in particular a window sill sloping backwards. After twenty years it was oozing decay.

We rebuilt it in a week this summer using decay resistant but economical details. Sawn fence posts are directly glazed with 4mm sheets of toughened glass. I love that ambiguity of the frameless window - the magic of the invisible cloak. The sheets drain over a simple aluminium flashing over open jointed Douglas Fir cladding, all detailed to keep everything beyond the air barrier nice and well ventilated. The roof overhangs and protects the wall - no gutter needed here so we could make an exceptionally thin edge for a built up felt roof. This is a detail 'under test', taking advantage of a self-adhesive felt system where a simple aluminium angle is primed, making the felt stick tenaciously to it. The test is to see how long this really does stick. In the meantime it is as razor sharp as any modernist could desire.