Architect John-Barry Lowe’s award winning home in Dublin is designed to achieve Passive House standards of airtightness and is the first private home in Ireland to be built using cross laminated timber.
TEXT Eve Dennehy IMAGES Andrew Campion
In 2023 Architect John-Barry Lowe and his family moved into their new home in central Dublin. After overcoming some major hurdles along the way, the story of Teach Spruis (Spruce House) starts at the beginning of the first Covid lockdown in 2020 – just as John-Barry and Carol were finalising the purchase of the site. However, John-Barry’s inspiration for the family’s new home goes back a lot further and incorporates key influences taken from having grown up in Dublin’s classical Georgian architecture as well as the period architecture of Berlin and Madrid where he lived as a student.
“I have wanted to build my own home since I was inspired by a ‘house of the future’ design project in my fourth year at the School of Architecture, University College Dublin,” says John-Barry. “It was in the 1990s, just at the beginning of awareness about the need to create homes that worked for modern society and the environment. The brief specified that we should design modest homes of 125m2 which seemed to me to be the sweet spot for most family units, and I decided there and then that I would like to make this the template for my future home.”
The result of this almost life long desire is Teach Spruis, a two-and-a-half-storey family home in central Dublin which is designed to achieve Passive House standards and is the first private dwelling in Ireland to be formed entirely of cross laminated timber (CLT.)
The Lowe’s purchased their small site with existing planning approval for a two storey flat roofed house that had been designed so it would not compromise a neighbouring house’s window, which is unusually set within the gable at attic level. The design, however, didn’t efficiently maximise the site so John-Barry created a new design which would work better for his family and this passed planning without a hitch.
“A key design factor was maximising the living space on the small footprint and creating flow and connection between spaces. I didn’t want to design anything that was superfluous or wouldn’t meet my expectations once it was completed. Most of my professional work in the past 20 years has been about renovating existing houses in Dublin, so I was aware of the limitations this can place on the design and construction and I didn’t want to have those constraints on my own house,” he explains. “I’ve also seen how easy it is to become obsessed with labels for rooms so that you can end up building a room for each function. Ideally I wanted to accommodate the various functions in as few rooms as possible, which would allow for the creation of a more varied set of rooms of differing scales and qualities, unfettered by specific functions.”
Having lived in numerous properties including some in Berlin and Madrid, all built in different periods, which he describes as his ‘university of life in buildings,’ John-Barry has taken learning and inspiration from each period, but his true passion is for Georgian architecture – he grew up in an exceptionally spacious Georgian house in Dublin and has his current office in a Georgian house. “It’s impossible to spend time inside Georgian buildings and not have characteristics such as their quality of light and high ceilings affect your designs.
“I have definitely incorporated learning from all the different places I’ve lived into the design of Teach Spruis, especially the Georgian influences such as maximising light wherever possible and using ceiling height variations. Even though the house seems quite compact from the outside, internally the living space is up to four metres high, whereas spaces like the mezzanine and bathrooms have lower ceilings and this combination works really well.”
The house is in a relatively inner-city neighbourhood located off a main road on a very quiet ‘Lane’ known as Avenue Road. ‘Lanes’ are part of Dublin’s architectural vernacular. They run in between both the grand historic streets and more humble streets which were built around Dublin’s canals between 1750 and 1920, originally providing rear access for the ‘big houses’ and accommodating their stables and garages. Over time mechanics, furniture makers and printing businesses moved in and many of these workshops still exist which adds greatly
to the mix between the people who live and work there.
Teach Spruis is the second last dwelling on a terrace to be developed on Avenue Road. The houses here are set back from the thoroughfare and this has allowed the Lowe’s to incorporate a front outdoor space including a parking space and a bike store as well as a rear garden. “Our outdoor strategy for the house was for two outdoor spaces or ‘rooms’ in the sense that they have walls high enough for the outdoor space to feel contained. A third outdoor space on the roof gives a surprise as you mount the stairs and brings light in from above.”
On entering the house the ground floor is arranged around a south facing double-height central space at the front and kitchen/dining room to the rear. Three upper half-floors contain three bedrooms and a mezzanine study which are stepped around a central stair that subtly links and merges the living spaces with short half-storey runs. The stepping upper floors have created a house in section that is inspired by the architecture of Adolf Loos, an early pioneer of ‘raumplan’ architecture where the proportions of each room are optimised to suit its function.
As Loos advocated, the house has a simple external appearance without any unnecessary ornamentation, while the interior in contrast is much richer and celebrates the natural patterns of materials, in particular wood, brick and stone. The richness of the interiors was also inspired by the famous Californian Case Study houses built between 1945 and 1966, of which the Eames House by Charles and Ray Eames is probably the most famous.
The north/south light across the plan has been carefully considered. Ground floor living spaces are connected by tall double doors that bring in light from the south to the north side of the house. The upper floors benefit from a large window onto the terrace at the top of the stairs and roof lights that bring light deep into the centre of the 12m deep plan. “The roof is quite low so gets a lot of sun for three seasons. The window and the door out from that on the north side of the house is fairly large, which for Passive House might be considered irresponsible, but it was important to put that window in that location to get the terrace and the house to work together,” John-Barry explains.
“Our overall design concept was for two large social or family rooms, one at the front and the other at the back with indoor/outdoor spaces which can work separately or in unison,” he continues. “To avoid changes in level or anything that would compromise the flow of those two big spaces we stayed with the simplicity and elegance found in most period Dublin homes which generally have interconnecting front and back rooms.
“We decided to dispense with the traditional hall and staircase arrangement which normally dominates houses. Hallways often don’t have much character; they’re not generous spaces but seem to rob the house of other useful space. Here we’ve woven the vertical spaces into the house in a way that we feel makes it more interesting and experiential.”
The spatial and functional concept of the design is traditional with bedrooms upstairs, living rooms downstairs and a mezzanine in between. “The bedrooms are quite modest. If you’re only building 135m2 it makes sense not to put your space into bedrooms and to put more space into the communal areas. We have used part of the roof space to create more volume, though from the outside it looks like a two storey house with a pitched roof.
“On plan there is a wide strip for the living spaces and a narrow strip for the kitchen, bathrooms and service spaces. I designed the kitchen and bathrooms to be close together to allow for very short pipe runs and to make the plumbing function well. I don’t like voids in construction, partly because it’s a waste of space, but also because if there’s a void anywhere near the outside of the house it can lead to potential heat loss or condensation issues,” says John-Barry. “The plumber and electrician weren’t particularly happy about this as it means less space for cables and pipes. To have a two strip design like this requires a minimum width of 5.7m internally. Using CLT for the superstructure helped with this because CLT walls are up to 50% thinner than those of standard masonry construction.”
When it came to the build, they were fortunate not to face any major site constraints. “The Lane at 6m across was wide enough for the CLT delivery truck to drive down. There was also enough space at the front of the house for the mobile crane, however with the house occupying 50% of the site and the removal of the old garage – except for two walls which we retained for the garden enclosure – we were left with nowhere to store materials,” explains John-Barry. “We were very lucky that our neighbours were happy for us to use their garage for storage during the construction phase. This was a blessing especially as we were building on a tight site at the same time as procuring materials.
“Unfortunately, we had a lot of supply chain issues including fluctuating prices, quantities and supply line closures. Not only were we dealing with Covid, but it was post-Brexit and there was still a lack of clarity about the delivery routes on the island of Ireland as well as a shortage of materials – particularly rockwool insulation. These delays of materials and some huge price increases made it a very difficult aspect of the project.,” John-Barry continues.
“Once we were up and running with the build though, our mass timber specialist G-frame Structures’ team of just three operatives were onsite for a total of only eight days to install the entire superstructure, which is kind of extraordinary. It had taken eight months of planning followed by just eight days to see the form of the house realised. The speed plus ease of the CLT installation was definitely the high point of the project.” he adds.
Teach Spruis has achieved Passive House standard of 0.55 ACH airtightness. Although CLT is recognised as having inherently high airtightness, it wasn’t really part of the Passive House strategy. “It’s important to note that with CLT every junction has to be taped either on the inside or the outside, though a lot less tape is needed compared with timber frame,” John-Barry explains. “It was difficult for us to access the rear of the structure externally because of our position up against a neighbour on one side and a garage on the other, so we designed some of the junctions to allow for them to be taped on the inside. G-frame took on the coordination and application of the taping while they were onsite, which they wouldn’t usually do.”
In addition to excellent airtightness and high levels of insulation, MVHR (mechanical heat recovery ventilation) and triple glazed timber windows were other important elements of the Passive House design. The use of heavy materials internally such as brick in walls around the staircase and ceramic planks supported on glulam beams in the dining room ceiling helps to further prevent overheating in the house in the warmer months of the year. On the south facade the visible brick confined to the ground floor facade helps define an enclosed outdoor space and on the north facade it has been used for the full height to give that outdoor space a special theatrical stage-like quality. Lime mortars have been used which allows the brick to breathe when used in cavity walls with the CLT and rockwool. The use of lime will also allow the brick to be recycled in the future.
The sensitive material palette includes an exposed CLT finish for the ceilings and at least one wall of each room and much internal joinery which creates a warm, welcoming aesthetic. Around the mezzanine, shutters formed of finer profile CLT allow users of the space to connect or disconnect with family life as required.
“When you design and build your own home you’ll constantly be noticing little things that you want to change or improve, but we love our new home. The exposed wood gives the house a calming mood, as if you’re out in nature rather than in the city centre. The high ceilings and natural light contribute to this feeling and due to the Passive House design and build quality there’s always a comfortable temperature wherever you are in the house,” says John-Barry
“In material terms the exposed brick, CLT and glulam beams give a feeling of richness which is enhanced by the outdoor spaces with plants and stone. It’s a lovely palette of materials to live in, it’s very unusual and even though there’s a continuity, you can have a lot of different feelings as you move through the house which was what I wanted,” he concludes.
Teach Spruis has gained recognition as spearheading the use of CLT in the private residential sector in Ireland. In 2024 it won the best Small Scale Private Building at the prestigious Wood Awards Ireland and was Highly Commended for the Sustainability Award at the 2025 Royal Institute of Architects of Ireland (RIAI) Awards as well as being shortlisted for the coveted RIAI Public Choice Award.