As the roof space is one of the key areas through which both noise and cold air can enter a building, ROCKWOOL insulation prevents heat loss and offers many other benefits too:
- Non-combustible – Rated Eurolass A1, our between the rafters insulation offers the ultimate peace of mind for loft conversions.
- Sustainability – our long-lasting insulation helps to improve your building’s carbon footprint.
- Instant benefits - No more cold draughts through cracks in the ceiling.
- Noise absorbing – reducing the noise of day to day urban life for a comfortable living environment3.
What is a Rockwool rafter?
Rafter insulation refers to the pitched part of a roof, which can be insulated with slabs or rolls depending on local availability. In some countries granulate is also used to insulate between the rafters. ROCKWOOL rafter insulation helps to provide thermal, fire and acoustic protection for roof spaces.
Can I put insulation between the rafters?
The general advice we give is that you should always insulate between and above the rafters (warm roof) or between and under the rafters (cold roof). On our U-value calculator, we don’t give an option for putting insulation between the rafters. But why not?
What are the benefits of Rockwool insulation?
When you place insulation above- and-between the rafter construction, ROCKWOOL solutions provide you with high acoustic performances. This can be a great advantage when building or renovating in areas with high sound levels, such as those close to airports.
How do you attach wool to rafters?
You will need to start at the top, stapling the wool material to the sides of rafters on each side. Carry on fixing the material until you have the whole space covered. You will need to have your dimensions correctly mapped out as you need to have material that covers the width of the rafter space.
What is the density of rock wool batts?
Can you put ductwork in the attic?
Does venting in attic help with moisture?
Is blow in insulation better than mineral wool insulation?
Can you use cellulose insulation in the attic?
What insulation do you use between rafters?
Warm loft. An alternative way to insulate your loft is to fit the insulation between and over the rafters – these are the sloping timbers that make up the roof itself. You can use rigid insulation boards, carefully cut to size, or you can have foam insulation sprayed between the rafters.
Should I insulate between the rafters in my attic?
In unfinished attic spaces, insulate between and over the floor joists to seal off living spaces below. If the air distribution is in the attic space, then consider insulating the rafters to move the distribution into the conditioned space.
Can you use rockwool for roof?
ROCKWOOL offers a range of products for installation both between and over the rafters. Offering more than warmth, ROCKWOOL pitched roof insulation also delivers additional peace of mind through its additional advantages of sound protection and exceptional fire resistance.
Can Rockwool insulation be used in attic?
This is one of the most cost-effective areas to add insulation. Use ROCKWOOL thermal stone wool insulation to insulate the attic of a new build, extension, or to increase the R-value and top up the current attic insulation, especially in an older home.
Can you put too much insulation in attic?
It's possible to over-insulate an attic as too much will cause moisture buildup and eventually result in mold. Eventually, adding more insulation leads to diminishing returns in trapping heat as well.
How do you insulate attic roof rafters?
3:378:37The Right Way To Insulate: Attics and Cathedral Ceilings with BattsYouTubeStart of suggested clipEnd of suggested clipPlace the craft faced insulation. Down between the joists on top of the drywall. And with the facingMorePlace the craft faced insulation. Down between the joists on top of the drywall. And with the facing down toward the interior of the house be careful not to compress the insulation.
Does Rockwool need to be vented?
Does rockwool need ventilation? If you don't ventilate properly, water vapor can condense and collect on insulation and rafters. This will reduce the effectiveness of rockwool insulation and could damage the house. Also, without ventilation, heat could penetrate into living areas during summer.
Do you need air gap between roof and insulation?
It is important that air is allowed to circulate between the roof covering and the insulation to avoid condensation - a gap of at least 50mm (2 inch) must be left between the insulation and the inside of the roof covering.
How do you install insulation boards between rafters?
0:121:36How to full fill insulation between and under rafters in a pitched roofYouTubeStart of suggested clipEnd of suggested clipSimply install the correct thickness of insulation trim to suit rafter spacings. It should be flushMoreSimply install the correct thickness of insulation trim to suit rafter spacings. It should be flush with the bottom. And top of the rafters.
What are the disadvantages of Rockwool?
The only disadvantages of Rockwool are that it is not biodegradable and can be slightly more expensive than similar insulating materials like fiberglass and cellulose.
What happens if Rockwool gets wet?
2) What happens if ROCKWOOL insulation gets wet? ROCKWOOL insulation is moisture resistant yet vapor permeable. In the event the insulation becomes damp or wet, the insulation, when thoroughly dried, will maintain the original performance characteristics.
How long does Rockwool insulation last?
Made from cellulose or mineral wool, this type of insulation will also last as long as 100 years – but is prone to settling and compacting. It is also often used as a home to rodents, that can leave it ineffective and damp.
Should I insulate the roof in my attic?
Proper attic insulation can also keep your roof in better condition by helping to prevent ice dams and condensation. Your building codes may require you to have a certain quality of insulation. However, installing even better insulation is to your advantage and your roof's advantage.
Can I insulate the underside of my roof?
Open-cell spray polyurethane foam or closed-cell spray polyurethane foam (ccSPF) insulation can be sprayed along the underside of the roof sheathing to provide a conditioned and insulated attic space that can be durable and efficient in all climate zones (see Figure 1).
Is it better to insulate ceiling or roof?
If you are deciding between insulating the roof deck or the ceiling, Insulating your ceiling should be the priority. Not only is it easier but ceiling insulation is beneficial in a number of ways: Keeps the temperature in the building regulated. Saves on energy costs.
What is the proper way to insulate an attic?
2:473:31How to Insulate an Attic | This Old House - YouTubeYouTubeStart of suggested clipEnd of suggested clipIt's not as efficient right and ventilation is critical for most roofs right so just continuallyMoreIt's not as efficient right and ventilation is critical for most roofs right so just continually pack your insulation nice and tight against and go all the way across your attic.
When to use Rockwool insulation?
When you place insulation above- and-between the rafter construction, ROCKWOOL solutions provide you with high acoustic performances. This can be a great advantage when building or renovating in areas with high sound levels, such as those close to airports.
Why do you put insulation in between rafters?
Insulation between the rafters is commonly placed in between the wooden beams to allow for more headroom. Insulation on the inside or outside is added to further improve thermal, fire or acoustic requirements.
Why choose ROCKWOOL solutions?
ROCKWOOL rafter insulation offers maximum thermal and acoustic benefits as well as superior fire safety, helping you to create a comfortable living environment within your roof space.
What is rafter insulation?
Rafter insulation refers to the pitched part of a roof, which can be insulated with slabs or rolls depending on local availability. In some countries granulate is also used to insulate between the rafters.
How long does stone wool insulation last?
The natural power of stone wool means that our insulation will last for the lifetime 2 of your building, without any sagging or slumping.
Why is it important to insulate the roof?
As the roof is an area where up to 25% of heat can be lost 1, installing the correct insulation is important to avoid high energy bills and unwanted noise pollution. Find out how our insulation over, under and between the rafters can boost the energy efficiency of your home or project. Find Inspiration, guides and reports.
Where is insulation placed on a roof?
Insulation under rafters is placed on the inside of the roof’s loadbearing construction. Under the rafter insulation is often a few cm of insulation, in addition to the insulation that is placed between the rafters.
cdarcy
My loft has been converted and has two roof voids, whose vertical walls are about four feet high (below the main horizontal roof purlins) which are accessed by small (3ft x 3ft approx) cupboard doors. The tiles in the voids do not have a membrane (the house was built in the 1880s) and there are drafts blowing into the bedroom.
Alastairreid
That part of the conversion is supposed to be draughty, You should fit draught excluders to the doors and make sure the stud walls are properly insulated.
cdarcy
I am now thinking of attaching (staple-gunning?) a breathable membrane to the underside of the rafters to reduce drafts and 'catch' bits of mortar from below the tiles - I need to use the roof voids for storage, and want to avoid everything becoming covered in sand / dust.
DIYnot Local
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
When to use Rockwool insulation?
When you place insulation above- and-between the rafter construction, ROCKWOOL solutions provide you with high acoustic performances. This can be a great advantage when building or renovating in areas with high sound levels, such as those close to airports.
Why do you put insulation in between rafters?
Insulation between the rafters is commonly placed in between the wooden beams to allow for more headroom. Insulation on the inside or outside is added to further improve thermal, fire or acoustic requirements.
Why choose ROCKWOOL solutions?
ROCKWOOL rafter insulation offers maximum thermal and acoustic benefits as well as superior fire safety, helping you to create a comfortable living environment within your roof space.
What is rafter insulation?
Rafter insulation refers to the pitched part of a roof, which can be insulated with slabs or rolls. ROCKWOOL rafter insulation helps to provide thermal, fire and acoustic protection for roof spaces. Made from natural stone wool, our products help to provide robust and durable insulation between, above and below the rafters, ...
How long does stone wool insulation last?
The natural power of stone wool means that our insulation will last for the lifetime2 of your building, without any sagging or slumping.
Why is it important to insulate your roof?
As the roof is an area where up to 25% of heat can be lost1, installing the correct insulation is important to avoid high energy bills and unwanted noise pollution. Find out how our insulation over, under and between the rafters can boost the energy efficiency of your home or project. Find inspiration, guides and reports.
Where should insulation be placed on a pitched roof?
Additionally, insulation can be placed below or above the rafter-line, depending on local requirements and the performance you are looking for.
What is the purpose of insulating a rafter?
Insulating the rafter space will give you a warm loft. This means insulating between or below the sloping beams that form the construction and support a sloping roof. The rafters are joined together by a horizontal ridge board at the top and tied together by ceiling joists at the bottom.
How much space between rafter and roof?
DIY rafter insulation. Before you apply the insulating material you will need to measure and leave a space of about 50mm between the roof (breathable membrane or tiled) and your insulating material so air can travel freely through, otherwise you could have issues with condensation and damp.
How much space between roof and insulation board?
When you use solid insulation board to create a warm loft the key thing to remember is ventilation – you must keep a 50mm gap between the roof and the rigid insulation board. We would always recommend having a breathable membrane in place between the tiles and the rafters too to allow the roof to breathe. If there is no vapour layer it might result in damp issues, since the warm air may condense in the loft space on cold surfaces. Water and timber don’t work too well together and it could result in the timbers rotting.
How far below the roof should insulation be?
You will need to have your dimensions correctly mapped out as you need to have material that covers the width of the rafter space. Make sure the insulation is 50mm below the actual roof, which can be done using the battens as your measuring gauge for the breathable area between the roof and the insulating material.
What is a loft lifter?
Another option are loft lifters, which are easy-to-install joist extenders that raise your loft boarding in order to allow extra insulation between your joists. Remember: safety should always be paramount. Stop working if you start to feel unwell and consult a professional.
How to handle wool in loft?
When handling wool, ensure you take enough rolls with you into your loft space. Use scissors to cut through the packaging and lay out the material. You will need to start at the top, stapling the wool material to the sides of rafters on each side. Carry on fixing the material until you have the whole space covered.
What to do if you are walking in a loft?
Ensure if you are placing heavy objects or walking in the loft space you have fix boards to your joists , otherwise there is a danger you may fall through the ceiling.
Why do you need insulation under rafters?
The rafters themselves will allow more heat loss than the insulation material, so the layer of insulation installed beneath the rafters is essential to combatting this thermal bridging effect.
What is Mannok thermoplastic insulation?
Mannok Therm Laminate-Kraft / MLK PIR Insulation has a kraft paper facing on one side and plasterboard bonded to the other side, making it ideal for use below the rafters to reduce heat loss through the roof and eliminate thermal bridging through the rafters.
What is the underlayment of a roof?
The more traditional method of roof construction is a ventilated roof, where the underlay is a traditional high resistance sarking membrane.
Can insulation be installed between rafters?
Insulation can be installed between the rafters using a ventilated roof construction or an un-ventilated roof construction. The decision on which method to use is usually dependent on the sarking, or underlay.
How much air space between felt and insulation?
You need 50mm airspace between felt and insulation. We use 100mm kingspan inbetween and 50mm fixed underneath
Can you use celotex insulation on a roof?
I would personally use celotex cut tightly in-between the rafters. You need to leave a gap to the rear of the insulation between the membrane and the insulation to allow air to circulate around the roof space. You could then simply clad the area with plasterboard etc.
What is the density of rock wool batts?
Rock wool batts are very comparable to 1.8lbs density fiberglass, which was simulated at R30 in that study. Denim batts would be comparable to cellulose in moisture buffering.
Can you put ductwork in the attic?
If you want to build a “good home”, do NOT put ductwork or other mechanicals in the attic. Keep all your ductwork and plumbing, and as much of the electrical wiring as you can, in the INTERIOR walls and floors. Avoid using the attic space for anything.
Does venting in attic help with moisture?
Be sure to block off any attic venting if you go this route, even if you also have insulation on the attic floor. In zone 2A Texas attic venting puts far more moisture INTO the attic than it removes. If the attic is air tight to the outdoors, air conditioning the spaces below the attic will still provide some drying benefit (via vapor diffusion through the ceiling).
Is blow in insulation better than mineral wool insulation?
I’m a big proponent of mineral wool insulation, but it’s best in walls. Blown-in insulation is both better AND cheaper for most attic insulating projects.
Can you use cellulose insulation in the attic?
If you’re able to keep everything out of the attic, and vent it as described above, then you can use blown cellulose on the attic floor which is about the cheapest insulation available , and one of the best options for this type of project. Just be sure to do a good air sealing job on the attic floor prior to installing any blown insulation, and put some baffles out at the eaves to prevent wind washing.
