Passive House Design & Construction Decisions - part 5

The last 18months of the blog have been very interesting. We are getting about 400 hits per month with the most read post has been ' How much does a passive house cost to build' which really shows that there is a lack of good information out there about what (1) what a house costs to build and (2) how much extra a passive house would cost.

Well we've been in the house now for about 5 months now and it have been an interesting time in terms of wrapping things up and perhaps areas where we would do things differently.

Paint

The main  lesson learnt on paint is to buy the best you can. Secondly it takes twice as long as you think it will, & even more if you have the final floor coverings down. We went for water based paint from Colortrend ( International Paints) based in Celbridge Co Kildare. They distribute through a limited number of suppliers who make up the colour in a mixing machine in the quantity you need, the paint is amazingly hard wearing . A stunning range of colours and better value than other high end suppliers like Farrow & Ball. We rolled the entire house in an obliterating white emulsion as soon as the plaster was dry. We did all the woodwork in a Colortrend water based mid satin off white; if I were doing it again I might more seriously consider a gloss for the woodwork given the proliferation of little mucky hands everywhere.

Building Drying Out

There is a tendency when wrapping up a build to rush the finishing, especially the installation of doors , skirting, architraves etc. Well, whatever you do dont rush it. The building when the second fix carpentry is installed should be very dry , in particular any plaster be well pink. Secondly, the timber should planed / treated / knotstopped before installation but also let sit in the building for a few weeks so that the moisture content stabilises to that of the building. If the moisture content is higher then than the building, the the timber will crack as it contracts as it dries out. Your tradesmen will want to rush to get finished, so order in time & its well wort waiting.!

Buying on the internet

We bought a number of items on the net, in particular the branded sanitaryware & taps from a German website ( mainly http://www.reuter-badshop.com). Given that the products are branded ( mainly Duravit) with international warranties ( check this before buying) then once we ordered the correct items then there was actually little risk. Furthermore if you pay using credit card then you have protection should faulty good be delivered , for up to six months. The prices were 40% less than here in Ireland but there was an 8 week lead-time on some item but in stock items were delivered in a week. They were excellent with questions We did buy some mid level taps from a UK website and that experience was less positive as the quality of the goods was simply lower than the German products. So in summary, buy good quality branded goods on the net, for mid level products then buy in the trade outlets locally.

Choosing Tradesmen

We have has a really mixed experience with our tradesmen. My lesson is document what you have agreed in advance & either email it or both sign it. Such a document means that an alterations from it will need to be documented so else you end up in a ' he say....she says....' situation eventually. No matter how convivial it all is at the start, there will be moments were selective memory will kick in. Always ask for references & check them out. In general, I would suggest buying the material for tradesmen and getting them in on day rates for the work & then monitor the quality. This is generally cheaper than a lump sum where you don't have transparency on pricing or material quality Finally, I would always suggest using tradesmen that are local, meaning within a 1 hour drive, in particular the plumber, roofer & electrician. These should be people who value their good name & have a vested interest....too often these days the work is ' hit & run' All of the above seems like common sense, but it is something that is often forgotten. To say that we were let down by many of our trademen would be an understatement, inlcuding the roofers. At the other end of the spectrum has been the electrician, Tommy & Maurice Whelan of Marathon Electrical, who have done a great job and stand over their work.

Documenting Your Build

This is absolutely key and should involve buying a small handheld HD video camera & a good high rez camera with a flash ( not a phone). The price of both would be around €200 on amazon. You should aim to regularly walk all the building walls, exterior, roof, scaffolding, skips etc... twice per week to show (1) progrees (2) technical details as they are being constructed (3) materials on site with batch / quality marks. We have had cause to produce some of these photos already & they were simply invaluable.

Gardening

Even though we're in the house a few months, some parts of the garden were planted over a year ago. If youve a large area to plant then its best to use bare root plants or whips ( little bare root trees). These take a while to develope but are a fraction of the price. Likewise now that the construction boom is over, there are many plant nurseries ( not gardencentres!) that have root balled trees - many of which can be 6m tall – which can be planted & have an immediate visual impact. All these type of trees / shrubs need to be planted by the start of April and well watered in their first season. Trees like silver birch are typically used in passive houses to give solar shading during the summer months to reduce building overheating. Gardening lesson over!

Paths Around the House

We put a 750mm concrete path around the house with a small quantity of smashed glass & pebbles pushed below the surface when it was drying. We will grind this back a few millimeters to give a polished concrete finish & the fall is away from the building of course. Between the build and the path there is a large gap with a land drain below the surface with a covering of grey pea gravel. We put the structure / pad in for a patio down too as this involved some heavy equipment and if done in the future would have shredded the lawn that is about to be planted.

Lighting

The best value & designs are to be had by going to the trade lighting outlets who will stock enormous ranges from the likes of Philips & Massive. These sellers do not have retail outlets but have good catalogues with all the dimensions. I would say these suppliers are 60% less than the usual lighting centres we all know. Have just done an exercise of replacing a few halogens with LEDs. Got these online from futureled.ie and whilst the quality of the bulbs if great, the light from LEDs is a harsher white. I did order warm white LEDs which are supposed to mimic the yellow of halogens but even then the 3 types I did order, each have a very difference ' warm white' colour, so do definitely order the LEDs in small quantities first as they do cost about €6 each. Switching the bulbs is a very straighforward job. The electical power saving is incredible; for example I replaced 50W halogens with 3W LEDs & the latter are actually brighter than the halogens.

Will keep working through my list of observations on the design and construction of the house. If there are certain topics you would like to see addressed, then let me know.