Sunday 20 May 2018

Extensions: plan for success

Short of space? Trapped in negative equity? Building on to your existing home can add value and space. But plan your extension carefully, says Caroline Allen

Malahide extension by Amanda Bone Architects
Malahide extension by Amanda Bone Architects
Fin walls on the ground floor give light but also shade and privacy, while a cantilevered first floor provides an enclosed roofed terrace which can be used year round. Photograph by Alice Clancy
Malahide extension by Amanda Bone Architects
Malahide extension by Amanda Bone Architects
Malahide extension by Amanda Bone Architects
In this Tipperary extension by Open Architects, light and privacy were priorities
In this Ailesbury Road project, OC Architects replaced a rear extension with a design clad in copper, which had been used in the original house

Caroline Allen

If, like many of us, you are feeling the squeeze in your living space but can't afford to move, or don't wish to, then consider the option of adding an extension. A well thought out extension can not only improve the way you live but can add value to your home.

The most-wanted list

So what are the key aspects to consider? For most homeowners, top of the hit list is to increase their living area. They want flexible, open-plan, multi-functional spaces that can also be separated or closed off in sections when required, says Amanda Bone of Amanda Bone Architects. "If it's not physically possible to divide up the open-plan area, you could make a distinction between the various spaces through changes in the floor-to-ceiling heights, the floor levels, the light levels, materials or views," she suggests.


Homeowners are also concerned about future-proofing their house and that means designing spaces that can change function over time as the family grows, says Bone. Tougher Central Bank regulations mean that grown-up children may take longer to fly the nest or may wish to move back home to save deposits.

"Design that will allow or provide for future use, in particular to accommodate adult offspring is in demand," agrees Bone. "Accessibility is another issue, especially with regard to the provision of bedrooms and bathrooms on the ground floor - ensuring that the house can be used by the elderly or the inhabitants in the future," she says.

Patrick Gilsenan of PG Architects agrees. "Extension proposals generally look for the open-plan layout. However, people are thinking about the future and ways to separate or break up the open-plan space later such as sliding pocket doors, bi-fold doors or a large pivot door or movable walls."

Going green

With water charges, high energy bills and the threat of climate change, it comes as no surprise that, according to Bone, homeowners are increasingly interested in sustainability issues, energy efficiency and extensions that reach passive house requirements.

Then there is the eternal need for additional storage - particularly for those with young children - to accommodate the "stuff" that we seem to accumulate.

Light touch

Maximising light is also on many a wish-list. "Light in the extension is key," says Claire McManus of Open Architects. "Think about where the sun will be throughout the day. Side windows and skylights should be considered." There are clever solutions for light in buildings where privacy may be an issue. In one of Open Architects' Tipperary house projects, fin walls allow light in but provide shade and privacy from the road.

Bone recently worked on the refurbishment and restoration of an Edwardian Arts & Crafts-style detached three-storey dwelling where a fully glazed and roof lit extension of only 4 sqm was added. "This intervention along with minor alterations to the ground floor layout significantly increased the light levels, transforming the living areas in this part of the existing house," she says.

The garden room

Many extensions push out the rear of a house and in these cases, integrating the house with the garden is a priority. "Unlike large buildings like hospitals, you should feel connected to the outside in your house," says McManus. "Everybody talks about bringing the garden in, but what about bringing the house out? Garden rooms work really well as well-defined spaces with hard edges within the garden. A house extension we did in Tipperary is an example. The cantilevering master bedroom provides a roofed terrace area outside. This means the garden can be used in most weather conditions, as well as giving a feeling of enclosure."

The law of unintended consequence

"When extending to the rear, watch out for what becomes of the rooms currently at the back of the house," McManus says. "Rooms that enjoyed light and connection to the garden, without careful consideration, could become dark over-sized corridors between the front and the new extension. Consider how they will be used, furnished and lit. Perhaps a different function could be considered such as downstairs bathroom, utility room or perhaps a small courtyard bringing light, views and fresh air would be a better use of space."

The aim should be to seek to get as much as possible out of the new space, according to Gilsenan. "A link or hall between rooms does not just need to be a corridor - it should be treated as a multi-functional space with a recess for a desk, bookshelves or a play space for children," he says. A utility area and hall can be combined, with floor-to-ceiling doors providing separation, McManus suggests.

Side extensions can be dual aspect, inviting light and views from the front and rear of the house, McManus says. "Often there's scope for a high ceiling or skylights. Planning permission is needed to extend to the side, but if you have the space, it's worth considering."

Pause for thought

Before you rush out to find a builder, Bone suggests pausing to ask whether you actually need an extension at all. Gilsenan agrees: "Always look to maximise the use, layout and space in the existing house. People often extend their home when rooms in the existing house are under-utilised."

A typical trap can be to automatically think you need more space or a large extension to accommodate your needs, says Bone. "I recommend first looking at how you use the existing rooms and how a reconfiguration of the existing layout could improve your situation. Extensions should be well-designed spaces that are considered, not only with regard to client requirements, but also to the existing house and context in terms of scale, proportion and materials."

McManus points to a recent two-bed apartment reconfiguration she designed in which the client lived alone. "Living space was cramped, with one bedroom hardly used. We opened up the second bedroom into the main living area, providing additional space and westerly light. Floor-to-ceiling sliding doors allow the area to be used as a bedroom when needed."

Says architect Stephen Musiol of Small Spaces: "Sometimes there are untapped advantages - sunlight, a view, connection to the garden - that don't require building a new space to be fully made use of. And sometimes a very specific new space can have a transformative knock-on effect in a house, without the new space itself being very big. The key is to think about the whole house and how it works for you or doesn't, and then formulate a plan of action based on that understanding."

The paperwork

And lest you forget, there is a raft of statutory requirements to be considered before starting an extension, according to Bone. The list includes the Building Regulations; the Building Control Amended Regulations 2014 and 2015 regarding client responsibilities, appointment of competent people and statutory certification for building control; the Safety Health and Welfare at Work Construction Regulations 2013 and planning regulations. "Another area to be informed on is the Home Renovation Incentive (HRI) which provides an income tax credit at 13.5pc of qualifying expenditure on repair, renovation or improvement works carried out on main residences by HRI qualifying contractors." (See our feature below.)

Planning issues must be borne in mind. These may include whether the dwelling is a protected structure, whether the proposed work is an exempted development and if so, whether it meets the requirements. "Other questions include whether it's located in an architectural conservation area (ACA) and whether the proposed work complies with the development plans. I always recommend having a pre-planning meeting with the planning officer to discuss the proposed works and to get their opinion prior to submitting an application," says Bone.

"In general, rear extensions up to 40 sqm don't require planning permission, subject to complying with rules and certain thresholds, such as size and height. This exemption does not apply to protected structures," Bone says.

The team and the timing

An array of professionals and tradespeople will potentially be involved in an extension build. The design team could include: an architect; structural engineer; mechanical and electrical engineer; quantity surveyor; project supervisors at design and construction stage; design and assigned certifier; and landscape designer.

It's important to allow sufficient time for each work stage as rushing through the project will affect the quality of the work and increase costs, warns Bone. Allow the brief to develop and change over time with regard to the proposed design in terms of what is right for the house.

Counting the cost

"With budgets, homeowners need to be aware of and allow for the cost of the works that will be required to the existing house when building an extension," says Bone.

"When budgeting and prior to the works being designed, allow €1,800 per sqm excluding VAT at 13.5pc upwards for refurbishment works, and €2,500 per sqm excluding VAT upwards for new build works," says Bone. "Other costs to factor in include design team fees, VAT and future tender price inflation of approximately 7.5pc. The design team fees and construction cost will be reflected in the quality of service you receive."

From super-sized statement pieces to more modest extensions, there's plenty of scope for imaginative design in building out, says architect Claire McManus.

"It's wonderful to come home to a beautiful place that has been designed around how you want to live - that's the value an architect brings to a project."

For a registered architect see

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