Creating a "passive" future: Some of the hidden issues with going "passive"

Now that we are getting to the "pointy" end of finishing the core building construction and moving onto the decorative finishes side, it became apparent that there are clashes with some building elements and the core basis of a passive house.

Three areas have presented themselves thus far, and there may be more still to come ?

a) Plumbing mixers- we had selected a plumbing mixer about 6 months ago for our shower/bath. When the plumber came to fix it this last week he found that there was a very small walling gap in which to locate the main part of the mixer, which would have meant the surround protruding some 40mm in front of the tiles!! After a lot of chasing around suppliers an alternative was found but this was a different design so all our matching tapware for the bathroom had to be changed to match- so much for planning and purchasing items in advance !

b) Ceiling speakers- our sound expert was advised by the builder during his pre-wiring that what he intended to do in the ceiling would not be permitted as it breached one of the Intello barriers. He had to hunt around for a technical solution which eventually came in the form of a special accoustic box.

http://www.dynamat.com/architectural-home/architectural-home-dynabox/

A 432 x 305 rectangular hole is cut in the ply above the speaker, into which the Dynabox is inserted and leveled to the top of the GIB. The speaker cable is fed into the box though a tight grommet, and the sides of the box are sealed with your black adhesive tape. Once the GIB goes and the speaker hole is cut, a bead of silicon or glue goes around the edge of the hole, sealing the box to the top of the GIB. The speaker can be later installed with a minimum of sound or air leakage into the roof space above.

c) Recessed cabinets- in our ensuite we had thought to have the bathroom cabinet recessed into the interior wall, until we found that it was a bracing wall and the recessing permitted is very limited. Whilst not entirely a "apssive" feature it does show that there is a need for a stage in the final architectural design where special fittings should be discussed and any modifications made to accommodate these.

We have had the first passive air test the other week, which "passed" but showed that some elements, e.g. the thermally broken aluminium front door, had more leakage potential around its hinges than was expected.

The house has been "gibbed" and the plasterers are now in starting work so the shape of the rooms is now a lot more defined, so we have done our own check this week to ensure that our plans for where furniture would go will work- seems to be OK !