How do I go about building a passive house? Where do I start?

How do I go about building a passive house?

Just like getting anything started, considering designing, organising & building a house from scratch....to be honest its a massive undertaking.

• There are simply so many variables from
• Knowing the budget including site works, fees, development levies?
• How big a house do you want, how many bedrooms etc...?
• Is there a particular layout that will suit you best?
• Are there particular planning concern/?
• Any neighbours , site, views, prevailing wind or boundary questions?
• Do I need to install percolation areas for waste water treatment?
• Can I afford the 10% premium for a Passive House over a house that meets building regulations ( budget for €1250 to €1400 per square metre for the house finished)

Understandably, the first port of call for many clients is a local architect, planing consultant, draughtsman or engineer to go about putting together some sketches, drawings & then a planning application. These professionals are very experienced in knowing local issues & will hopefully guide you through this process. This is very important as it sets the scene for the big decisions....don’t worry, there will be hundreds of smaller decisions to be made. They as very experienced in understanding client requirements & potentially bring real design & flair to your new home. However, just before you agree to pair up with the local professional for the complete build ….I would advise you to stop & ask a few questions to make sure their experience matches your end goal.

As you will see through the build process & I have mentioned before, there are so many companies tradesmen & people who claim to experience in  building passive houses & their components : be that window installers, timber frame companies, heat recovery installers, plumbers etc..........but the reality is that the vast majority do not have such experience however well intentioned. Indeed, there is no uniform definition of what a Passive House is, so one man's B3 rated building with fancy add ons or eco-bling is another man's super low energy passive house. In my opinion you need to recruit people & companies with the right experience to the job & who can get someone to answer the really detailed technical issues as they arise if they cannot themselves.

Even if you are planning on building a 'low energy house' the question is even more acute as there really is no actual agreement on, It all sounds a bit like there is no uniform agreement on what a fuel efficient car is – is it a 0.7 litre Toyota Yaris car or a 2.5 litre Lexus Hybrid

Speaking with an architect you visited our home recently , he was quite surprised at how technical & detailed the design and construction process for a Certified Passive House. He was very impressed at the outcome that achieved. What this means is that each component of the build needs to be really considered & details resolved well before the contract starts building it. This may sound obvious , but in construction most tradesmen just want to crack on & do what they always do, be that right or be that wrong for your case. In the case of a passive house you need to ensure that that the building, and all its installed components, that you submit for planning is capable of being built cost effectively as a passive house & there are no surprises. You have to make sure that the house you get planning permission for can actually be built as a passive house - the most common issue I have seen in Ireland is the inclusion of dormer windows in houses which are extremely difficult to airtight & remove thermal bridging

The example I always think of is a car. if you have a house design & want to make it a passive house, this is a bit like taking an existing car design & trying to make it a fuel efficient car. However, if you can rewind & make sure that the car design was efficient in the first place, then ensuring that car the leaves the production line is fuel efficient is a whole lot easier & potentially cheaper.

If you want to build a passive house then there are a host of specific considerations, which include:
Location of the heat recovery & associated ducting
Location of the airtightness membrane & insulation layers
Location of solar panels, tanks etc..
Reduction in summer overheating & introduction of shading
Reducing windows on the north side & optimising the quantum of glass on the south side
Optimal room locations, so that rooms that don’t need much solar heating e.g. bedrooms are not on the south end

So , to answer the question I posed at the start, I would advise the following:

Step 1 : Answer the big questions yourself if you can, go & visit houses that are open to the public, keep an eye out for International Passive House open day in chilly November. Scandanavian Homes in Galway have a great setup, are very welcoming, & whilst the design might not been to your own taste, they are extremely experiences & knowledgeable.

Step 2 : Either get the local architect / engineer / draughtsman to do up your drawings but make sure that they are reviewed in detail by someone which make sure that the house will work as a PH

Step 3 : Once you have planning permission, get specifications, drawings completed for the house, but again the specification should be written to ensure that the house will actually perform as a Passive House

Step 4 : Recruit a contractor who has actually built a passive house before & tie them into meeting the specification

Step 5 : Get people / tradesmen / companies / professionals involved who understand the specific detail required in a passive house e.g. detailing where the floor meets the walls, MHRV ducting layouts, airtightness membranes overlapping, to regularly inspect the build.

Step 6 : Upon completion of the final airtightness test & confirmation that the house meets the construction specification, submit the design package for approval as a certified Passive House.


In our experience there are few professionals who can supply that level of design support & site monitoring to your house build, be that a self build or a contractor build. One of the few practices I've found in the field who have that level of experience required to support the client, architect or contractor is Archie O'Donnell at Integrated Energy (www.integrated.ie). Archie & his team have many years experience in passive house specification, design & construction monitoring and much of their work these days is in assisting architects in delivering the level for required for a passive house

If I were to summarise succinctly what you need to do to start & finish a passive house build successfully, it is best done in the words of Ronald Regan ' Trust, but verify'.