RIAI Awards 2011 Best Emerging Practice: Highly Commended

Featured in – RIAI Annual Review 2011 & Construct Ireland 2011

View interior photos by Philip Lauterbach on www.plpix.com. The stylist for the photos was Penny Crawford Collins.


In this example, House Extension to the Rear, the creation of an exterior courtyard allows the one-storey extension to reach into the long garden. In addition the sunlight is captured and brought into the existing house by the courtyard without which the house would suffer from dark rooms. Two large wooden sliding doors at right angles marry the new to the old. The 70 square meter extension comprises of a galley kitchen, living room and corridor leading to a bathroom and bedroom, which form a courtyard of 20 sqm and terrace to the garden of 10 sqm. By removing the one-storey garage and utility room, we not only achieved separate access to the garden, but most importantly we restored the original volume and beauty of the two storey house built in the 1930s in one of Limericks most exclusion residential areas.

Sustainability in Design

Our approach to sustainability involves maximising natural heating and lighting solutions. This means designing spaces and openings according to their orientation. The roof of the kitchen and living room slopes towards the boundary wall, maximising the south west facing window surfaces for passive solar gain. The roof of the bedroom and bathroom slopes down towards the existing house, minimising overshadowing to the courtyard and two storey south facing elevation. The interior floor levels of the main house and the extension are continuous, except the bedroom which is raised by two steps to create a steeper angle of the grass roof. 3D sunlight studies determined the optimal angles required for the roofs for summer and winter time conditions.

Zero Waste Concept – 40% of our waste today is from our buildings

The Client was amenable to the idea of reducing waste by using natural and recycled or recyclable materials wherever possible. Starting at the substructure, Foam Glass Gravel recycled waste glass was proposed (regrettably not used because of sourcing issues). Besides its outstanding mechanical and thermal properties, foamed glass manufacture is an exemplary process for waste recycling on an industrial basis. Substituting hardcore, a layer of Foam Glass Gravel forms the base of the construction. On top of it lies a structural slab, thickened at the edges, made of reinforced GGBS Concrete. This is produced from a recycled industrial by-product from the manufacture of steel.

The super-structure is a Timber Frame Construction filled with Natural Fibre Insulations, sheeps wool and wood-fibre board from renewable resources, forming a Breathable Wall System (eliminating membranes) which allows for a natural regulation of moisture. The external cladding is of untreated wood and a breathable render system. The window frames are of solid hardwood. The waterproofing membrane for the roof, Sintofoil TPO/FPA is another environment-friendly product of a polymer base excluding chlorine, lead or other heavy metals, and is totally recyclable. And finally for extra warmth a Grass Roof was installed over the section of the bedroom extension.

Sustainability in Technology

In keeping with the high standard of natural materials and insulation, a natural gas boiler with a warm water collection tank were installed and connected to solar panels. The ground floor level has a new solid oak wood floor throughout with underfloor heating in the new part.

Completion 2010


This project has been featured in a number of publications. A few are featured on this site:

RIAl Annual Review 2011/2012 – Zero Waste

Plan Magazine – From Nenagh to Düsseldorf

Construct Ireland Magazine – Zero Waste Extension, County Limerick

Limerick Chronicle – Local Buildings In Awards Shortlist