OP21 Stella Maris, Family Home in Wicklow Town

Current status: 
Building Owner: 
Art McCormack
Consulting EuroPHit Partner: 

MosArt - Contact person Mariana Moreira

Existing treated floor area (usable floor space): 
135.00 m²
Original situation: 

This is a detached family house located on the edge of Wicklow town. It is orientated North/South where the main views to the sea are to the North. Towards the South there is a highly vegetated hill, hence projecting considerable shading to the South facing facade.

This house was original a 1960s county council bungalow house, built with concrete blocks without any insulation on all walls, roof and floor. In the 1990s this house was retrofitted and extended with a timber frame construction type. At that time the existing floor was retrofitted with 50 mm insulation and the walls were internally insulated with 50mm of fiberglass. It is naturally ventilated with the traditional vent/grids on the external walls. In 2009 a new gas boiler was installed along with vacuum hot water solar system. The gas boiler heats the hot water tank that feeds all radiators installed in every room. There is a wood log stove in the living room.

Modernisation proposal: 

The proposal is subdivided in several refurbishment steps. The first step will improve the thermal performance of the existing roof, insulating in between and above the rafters. An airtight membrane will run directly above the rafters below the new insulation above it. The existing block wall facing North will be externally insulated with rendered 250 mm EPS boards. The existing render on this block walls will be the airtight layer for this part of the building. The chimney will be externally insulated and updated to be connected to a wood log stove. New roof lights, widows and door to Passive House standard will be installed. The second step will improve the side (East and West) elevations where the timber frame construction is joining the previous block walls. The timber frame walls will be insulated between and over the the studs. The airtight membrane will be over the stud walls behind the new external insulation. Again, new windows and doors will be to Passive House standard. The third step will comprise a small extension to the South and the increase of the South facing windows (to Passive House standard) along with the improvement of the timber frame walls. A PH certified HRV will be installed in the insulated attic. Heating will be provided mainly by the ventilation system.

Efficiency improvement: 
PHPP verification sheet before retrofit: 
after retrofit: 
Current situation: 

On site works have started end of June 2015.

The South side of the slopped the roof is almost complete. 

The heat recovery ventilation system is installed in the attic and the ducting is now complete to supply and extract on the first floor of the house. The next retrofit step will comprise, among other measures, the completion of the ventilation duct work through the ground floor.  the ventilation system is installed on the first floor. 

Challenges of the project: 
The main challenge of this project is the detailing of the connection between the airtight layer along the timber frame construction and the airtight layer along the masonry walls on the front and sides of the house. The other main challenge is to assure that all details are thermal bridge free.
Construction photos (click to view gallery): 
Blower door test carried out before retrofit works start. Result n50 is 5.8 1/h
On site photos by MosArt
Connection details and thermal performance of the building (click to view gallery): 
Stella Maris
Ballyguile Beg
Co Wicklow