High Potential of Attic Conversions: Exploring Costs and Subsidies

Do you really know anything about that largely empty cavernous space hanging above your ears?

Here are just the basics as you get to know your loft and its lofty potential.

Insulation and ventilation

We recently talked about the need for at least 300mm of blanket insulation on your attic floor, and you can find details of the generous grant run by SEAI between €800 and €1500 here.

In addition to wrapping water lines and isolating any water tanks for a gravity-fed system, ventilation is key to managing condensation in your attic.

With modern tight construction and extra insulation on the attic floor (especially if it was installed with a condensation barrier), any moisture entering your attic can stay in the now relatively cold space and condense on surfaces. decay-promoting wood and your insulation materials, which could cause them to sag.

An attic loft living space concept. Image: Getty Images.

We need air exchange here like we do down here. If you find wet spots on the ceilings under your attic, you might have this problem.

If you’re upgrading insulation levels, now is a great time to check cross-ventilation measures to get any vapors out of the attic.

These would include soffit vents, running vents and even ventilation tile products.

Check if the vents already in place are not blocked by new insulation. The SEAI advises: “Long-term exposure to interstitial condensation in a roof space can lead to rotting of the roof structure. It is essential that a cold roof space is sufficiently ventilated”.

Read the full guide here.

Conversion rule

Building regulations exclude most domestic attics with pitched roofs (but that doesn’t stop people from going ahead with a conversion to a “storage room” that’s actually used as a dwelling).

Building regulations exclude most pitched-roof home attics.  Photo: Getty.
Building regulations exclude most pitched-roof home attics. Photo: Getty.

This is a controversial regulation rooted in the vital need for adequate exhaust and ventilation, especially in bedrooms, but many building professionals view the requirement for free space as obsolete in an age where we are desperately looking for more space in the building envelope, at low cost, without the need for planning.

Our understanding of healthy air exchange and available devices to keep the air fresh has improved incomprehensibly.

Willie Busteed, who runs specialist attic conversion business Busteed & Sons Attic Conversions Ltd (Cork) with his son Wayne, explains the process in more detail.

“Building permission for attic conversions is a gray area. We always advise all our potential clients to contact planning.

“Irish roofs, in general, have a 30 degree pitch which in most cases will not lend itself to class as habitable. Normally planning is required if you are converting to habitable or Velux windows need to be positioned in front or on the side of It is also required if a skylight is installed.

“To qualify as habitable, a certain ceiling height of 2.4m must be reached and this ceiling must measure half the width of the room in length at 1.5m diagonally. It’s complicated.”

Low platform beds fit perfectly into the eaves of that high ground where full reading space is paramount.  Wallpaper by Woodchip & Magnolia, Glycine Ardoise, €101.95 per roll.
Low platform beds fit perfectly into the eaves of that high ground where full reading space is paramount. Woodchip & Magnolia wallpaper, Slate Gray Wisteria, €101.95 per roll.

In addition, to be habitable, all ceilings on the first floor must meet a certain fire resistance, he adds.

“All doors on the first floor must be half-hour fire doors and the frames and stair clearance must be two meters and lead unobstructed to an exit, says Willie.

“We send all detailed customer measurements etc to our structural engineer who has to do calculations on the changes to the roof structure and he designs the steel beams to be used in each individual conversion and new roof restructuring so that they may approve its structure.

“We insulate to height standards of course. We also get certification from our electrician to make sure everything is tested to RECI standards.

“We do everything to modern standards, even if it is classified as non-habitable. Once the steels are in place and all the structural work is completed, our structural engineer visits and signs the restructuring even if it is non-habitable, giving to the owner complete peace of mind.

“We photograph all the work every day and clients have this and a certification if they decide to sell their property.”


Getting around the attic, especially without a proper “cut” roof, is hard enough, and usually a forest of killer trusses. Do not climb there without a mask, as the tiny particles created by dust and insulating materials can irritate the lungs.

Where you can floor, the attic becomes much more accessible and less stressful to visit. It is essential to ensure that the ground is stable and safe for beginners and to avoid ramming a bat or blowing insulation designed to trap pockets of hot air to remain thermally efficient.

Deep insulation can be higher than your joists. Just because you can see the joists doesn’t mean they’re stable enough to lay down the floor directly.

If in doubt, consult a specialist company or structural engineer for advice. While you’re struggling up there, make sure any recessed fixtures in the ceiling below are F-cap approved or installed in attic caps to keep them from overheating under your attic insulation batts.

You don’t need to cover the whole attic and you can add walkways to storage areas or say your PV array battery (if it’s high up) rather than covering every square yard.

You may need new floating joists which ensure that you are not stressing the joists resting on the ceiling at the bottom or pushing down your 300m insulation blanket.

Consider adding simple storage shelves in the eaves to lift all the boxes of stuff off the ground.

Flooring work must be followed by a certificate of compliance issued by an engineer to show potential buyers and surveyors that the work meets current building regulations.

Willie Busteed adds: “Over the last few years there has been a huge comeback from carpeted attic owners. Some would use semi-solid and solid laminate flooring. Prices for these all vary depending on the level of complexity of the fit and are priced individually.


Fire regulations regarding attic conversions are meticulous and will require a series of upgrades for an unfinished attic and its access. It would be wise to follow them even when planning is not required.

Chief among these is a regulation level staircase – it is not a pull-out attic staircase. The problem is often sacrificing space at the base of the stair to accommodate its footprint and height – ask your engineer or architect to review your plans.

Light and escape are things you will need to think about in any loft conversion.  Velux center pivots from €326 excluding VAT.  VAT and installation, on www.velux.ie.
Light and escape are things you will need to think about in any loft conversion. Velux center pivots from €326 excluding VAT. VAT and installation, on www.velux.ie.

Spoil that with a DIY disaster, and you’re looking at a major structural modification to skip planning now or in the future when your adventures are discovered by a surveyor.

In addition to providing new means of escape, you will install fire doors, fire resistant materials and a fire detection and alarm system in this second or third floor space – it all makes sense .

Otherwise, in an undeveloped storage situation, access will be via a ladder or retractable staircase.

What not to store in an attic

If the attic isn’t a finished space with heating and ventilation to a livable level, it’s likely to be subject to some pretty wild fluctuations in heat and humidity that you won’t experience downstairs.

Any open boxes should not be stuck there for long periods of time.

Most attics have at least one or two seasonal mice, so fabrics, paper, stuffed toys, carpets, leather, and upholstery are vulnerable to biting, as well as attention from moths, silverfish, beetles, wasps, as well as the droppings of bats and nesting birds.

Mold and decay can quickly set in due to the foul atmosphere.

Use rigid plastic boxes sealed with snap-on lids if you must put smaller, sensitive materials overhead, and periodically check their condition (even vintage clothes will rot in this setting over time). The Samla boxes from Ikea are ideal at €5.50 each.

It’s time to ask why, if these pieces are deemed so precious, fragile family photographs like treasures are up there. Reassign or erase?

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