How To Soundproof A Loft Bedroom
A loft bedroom is a great way to expand your living space, but they can lead to a lot of noise down below. When I converted my loft I decided to research how to soundproof a loft bedroom. Here’s a quick answer:
Unlike other rooms, the best tip for how to soundproof a loft bedroom is to focus on the floor. Adding lots of insulation, along with materials such as mass loaded vinyl, will drastically reduce the level of impact noise transmission through the floor.
In this article I’ll look at the types of noise you’ll be working against when soundproofing a loft bedroom along with the best ways to combat these issues.
Also read: How To Soundproof A Log Cabin
What Are The Most Common Noise Problems In A Loft Bedroom?
In a typical room you’ll generally apply soundproofing materials to the walls while concentrating less on the floor.
In a loft bedroom, however, the floor is a more important space to soundproof. After all, the walls of the bedroom are the building’s roof, meaning there won’t be much sound transmitting through them.
But you will need to block out external noises such as birds and traffic, so don’t overlook the walls!
Sound waves can be broken down into 2 main types. These are:
- Impact noise
- Airborne noise
Airborne noises are ones such as voices, TV, and music. These sound waves travel through the air and will pass through a solid surface when they make contact with it.
Impact noises, on the other hand, are caused by an object hitting a surface. Examples include footsteps walking on the floor above, and furniture being moved.
Impact noises are caused by vibrations passing through the object, which become sound waves when they reach the other side.
In a loft bedroom, your bigger problem will be impact noises coming from the bedroom, while airborne noises coming from outside and below will be a lesser issue.
When it comes to soundproofing a loft bedroom, adding in these materials will be much easier during the construction stage. Of course, you can make these alternations after the room has been converted, but it’ll be a lot more work.
The most important thing will be to add lots of mass. Mass increases the sound transmission class (STC) of a surface, but it’s most effective alongside materials that dampen and absorb sound waves.
For best results, you’ll need to employ all 3 principles when working on your loft bedroom. And the more planning you do before you start, the better the results will be.
How To Soundproof A Loft Bedroom
When it comes to soundproofing a loft bedroom, it’s worth focusing on all areas possible to maximize the effectiveness.
That said, there’s definitely an order of importance for where you should start. In my opinion, it goes:
- Floor
- Walls
- Ceiling
- Windows
- Door
This is the order in which I’ll address my soundproofing solutions, as it makes sense to start with the area that’ll provide best results. But I recommend paying attention to each, as they’ll all give you something.
1. Soundproof the floor
When it comes to soundproofing the floor in a loft bedroom, you have a couple of options. These are:
- Building a suspended floor
- Adding insulation
- Adding more mass
Building a suspended floor
This is definitely the most labor-intensive option, but will effectively stop all impact noise. It works on the same principle as decoupling a wall, just done horizontally instead of vertically.
Decoupling a wall involves mounting both sides on separate joists, which stops sound waves from passing through.
Building a suspended floor is basically the same thing, as you’ll lay the upper floor beams on separate joists to the ceiling below.
For this you’ll need the following (available on Amazon):
In exactly the same way as you’d decouple a wall, in this method you’ll lay the resilient channels along the existing ceiling joists and then attach the sound clips.
You then need to lay sheets of MDF over the top, which will become the base for your bedroom’s floor. Seal any gaps between the MDF sheets using acoustic caulk.
Alternatively, you can lay a new set of floor joists completely separately from the ones below. I’d recommend either raising them with a stack of bricks or by cutting holes into the walls.
The downside with this option is that it makes the floor much higher, which often isn’t a good thing in a loft bedroom. Vertical space is usually at a premium here, so the resilient channel method is likely better.
You’ll also need to fill the cavity with insulation, but I’ll cover that in more detail below.
Adding insulation
The floor cavity can be a big issue when it comes to soundproofing. The empty space basically acts like an echo chamber in which sound waves can reflect off the surfaces and reverberate. This can make them sound louder than they are.
Filling this cavity with appropriate material is therefore very important for reducing sound transmission.
Mineral wool insulation is perfect for this job. It has an open structure that absorbs sound waves. They get trapped inside and expend their energy moving the fibers. This converts sound waves into heat energy.
Acoustic mineral wool has a higher density than standard cavity insulation, so is much better at reducing noise transmission.
When laying it in the floor cavity, be sure not to pack it too tightly. It works best when not compressed, as this allows the sound waves to get trapped inside it.
Mineral wool is also great for thermal insulation, so this is a double bonus.
Adding mass
Finally, adding more mass to the floor will reduce noise transmission. Impact noises start as vibrations, so making a structure heavier means it’s more difficult to vibrate.
There are a couple of products that would be ideal here:
- Mass loaded vinyl (Amazon link). It has a weight of 2lb per square foot and is limp mass, meaning it doesn’t vibrate.
- Sound deadening mat(Amazon link). This is a very similar product made from butyl rubber, but has the advantage of extra thermal insulation.
Apply either of these products either under or over the floor surface. It doesn’t really matter where in the floor sandwich you put them as long as you lay a more attractive flooring over the top.
Here are some other tips for making your floor soundproofing as effective as possible:
- Thick carpet is very effective at dampening impact noises. Avoid hardwood flooring wherever possible.
- Similarly, a high quality carpet underlay will add another layer of sound damping to the structure.
- MDF is a good choice for a building material because it’s much less rigid than something like plywood or timber.
- If you need another layer of damping material, EVA foam gym tiles (Amazon link) are a good option. They can easily be hidden under the carpet too.
- Rugs might not do much, but they’ll make a slight difference if you’re still having problems.
2. Soundproof the Loft Bedroom walls
As I mentioned earlier, walls aren’t a particularly big problem in loft conversions. While you’ll still be able to hear traffic noise, it won’t be as bad as on the street level.
Generally speaking, airborne noises will be less intense when you’re on the 3rd or 4th floor of the building.
Therefore you won’t need to put as much effort into soundproofing the walls in a loft bedroom.
Here are some effective solutions:
Insulate the walls
Fill wall cavities with mineral wool insulation to improve sound absorption. This can be done whether you’re fitting walls in the loft or simply insulating the building’s existing roof.
Decouple the walls
As suggested above, you can fit isolating clips and resilient channels before hanging the drywall. This is less effort than building 2 sets of studs and will give almost the same results.
Adding mass
Alternatively, if the walls are already hung, you can add more mass to them. You can do this by adding another layer of drywall, or by using acoustic insulation panels.
Again, mass loaded vinyl and sound deadening mats are ideal here, and you can hide them under sheets of drywall.
While you can buy acoustic drywall, which usually has more layers and specialist soundproofing materials fitted, I’d recommend saving some money by simply using the products suggested above.
Don’t forget about pipes
Many older buildings have pipes running through their lofts, or in the ceiling cavity above their top floor. Typically this is because hot water tanks were fitted in lofts.
You might also have HVAC pipes running around the loft or other plumbing work depending on your building’s layout.
If you’re fitting new walls in your loft bedroom, be on the lookout for any pipes. These can be a big source of unwanted noise, as it travels quite well through pipes.
The best thing you can use to insulate them is fiberglass pipe wrap (Amazon). Avoid things like polystyrene or rubber pipe insulation. While these might be great for thermal insulation, they don’t do much for sound.
3. Soundproof the ceiling
Soundproofing the ceiling will work much like the floors and walls. In fact, in many loft bedrooms, the walls and ceiling might be the same thing.
Follow my advice of decoupling if you can, but if not then concentrate on adding as much mass and insulation as possible. This will effectively prevent sound transfer from outside.
Be sure to concentrate on small gaps, sealing them with something like Green Glue.
4. Soundproofing the windows
Lofts originally don’t have windows, so you’ll often find fairly modern windows in a loft conversion. This is a good starting point for soundproofing, as it likely means they’re double-glazed.
If you have the budget to upgrade, consider triple glazing. It’s not a significant improvement on double glazing, but it does add another layer of glass, and therefore another air cavity to reduce noise transmission.
I also recommend using weatherstripping to seal the edges around the windows where they meet the frame.
Weatherstripping is mainly for thermal insulation, but heat and sound leach through small gaps in similar ways. Blocking up any small gaps will make a difference.
You should also go around the window with some acoustic caulk too. Unlike normal caulk, acoustic caulk is more elastic and so will bend if the building ever shifts.
5. Soundproof the door
Like windows, doors are a common issue in soundproofing projects. The advantage in a loft bedroom is that the doors are often at the bottom of stairs on the building’s second story.
More than anything, this means any sound that transmits through them won’t be a big problem in the bedroom itself.
Even so, it’s worth considering some ways that you can make them more soundproof.
Your best option would be to add more mass to the door, as internal doors are usually hollow.
Mass loaded vinyl and sound deadening mats are the best choices for this job, and you can cover them with a layer of wood or fabric if you want it to look nicer.
Alternatively, you can hang some noise-reducing curtains (my top picks) in front of the door. They’ll help to dampen any noise that transmits through the door.
While not that effective, they’ll definitely muffle problem noises enough for them to not be a problem.
Finally, you’ll want to seal all gaps around the door and its frame. Install a door sweep (Amazon) to block any gap at the bottom, and use weather stripping around the frame.
As with windows, acoustic caulk is a useful product for any tiny gaps around the doorframe. You could also consider replacing the door with a solid soundproof door, but these can be very expensive.
Some Final Thoughts
When it comes to how to soundproof a loft bedroom, the process isn’t that difficult. Providing you’ve got some DIY knowledge, you’ll be able to do a pretty good job.
My best advice is to focus mainly on the floor, as this will be the biggest issue. If you can effectively block sound transfer from below through the floor then you might not have to go any further.
