Building Home Studio - concept plan reveiled - feedback?

kingrat wrote:

Not sure I follow your point about the bricks...

Woepsiee, I meant studs...

Figure 4 looks like it could be used for studio design in any part of the world, without issue, we just would make our internal framed wall decoupled from the concrete blocks.

So if I understand this correctly: I have to stucco the outside of my outer wall and paint this with latex paint. And on the inside of the outer wall I need to put rigid insulation. Then a small airgap --> then the rockwool (not too dense) + gypsum (+ green glue gypsum) --> is this correct?

That sounds correct. You should check this freedom with your local building inspectors though. The design in figure 4 relies on large moisture storage in the concrete block. The image looks like the block is a US style 8 inch CMU, concrete block. I'm not sure what kind of concrete blocks are available in the Netherlands. You wouldn't be able to replace the exterior concrete block design with timber framing and maintain the same moisture control. Dan

That sounds correct. You should check this freedom with your local building inspectors though.

What do you mean with 'this freedom' exactly?

The design in figure 4 relies on large moisture storage in the concrete block. The image looks like the block is a US style 8 inch CMU, concrete block. I'm not sure what kind of concrete blocks are available in the Netherlands.

I'm not building the studio from the ground (there is a picture in of the first pages of the building), so there will be no concrete blocks, but normal bricks/brickwork... So I guess this affects the moisture control quite a bit. If you know this, does the moisture control fashion in figure 4 still applies?

kingrat wrote:

That sounds correct. You should check this freedom with your local building inspectors though.

What do you mean with 'this freedom' exactly?

The design in figure 4 relies on large moisture storage in the concrete block. The image looks like the block is a US style 8 inch CMU, concrete block. I'm not sure what kind of concrete blocks are available in the Netherlands.

I'm not building the studio from the ground (there is a picture in of the first pages of the building), so there will be no concrete blocks, but normal bricks/brickwork... So I guess this affects the moisture control quite a bit. If you know this, does the moisture control fashion in figure 4 still applies?

Apologies, "freedom" was an auto completion error, should have said "design". I had forgotten that your build was not from the ground up sorry. Knowing this, have a look at your brickwork, is it a single skin? Ie. Not a cavity wall? If it is a cavity wall is it vented? ie. Are there vents at the top and bottom, or in between mortar joints anywhere in the wall. You need to determine whether you can use this wall as your outer leaf or not. If it's vented then you can't use it as your outer leaf and its very unlikely building control will let you seal it. If its single skin then you need to check with building control what is acceptable moisture control in your environment. Dan

Apologies, "freedom" was an auto completion error, should have said "design". I had forgotten that your build was not from the ground up sorry.

No problem!!

Knowing this, have a look at your brickwork, is it a single skin? Ie. Not a cavity wall?

It is a single skin wall, not a cavity wall. Actually, at this point, it is part bricks, part wood (sort of wood window frames). But the plan is to remove the wood and replace this with brickwork --> so we can use this as the outer wall. We do not have much space and with this structure we have optimal use of the space (and a real two leaf system). Because I'm not building something new, I don't have to worry about permits etc.. I have actually no idea where I have to ask about acceptable moisture control and what I have to ask exactly --> do I have to know what the average humidity is around here? Or something else? Average humidity in the netherlands is 80%. Let's see if I can find values of my area...

Here I am again... Was pretty busy with other stuff. Last few weeks I was starting to pick up this project again. I have gathered some information from a number of handymen and the basic plan is almost ready. I've dug around 40 cm into the ground. It's pretty moisty sometimes (after heavy rain). But that shouldn't be a problem. Before pouring concrete, I dig a hole in the middle and will pump the water away for a few days. Then I'll try to make the ground as equal as possible. Then I will put pond liner there, which rises a good meter on all sides. I lay 10 cm pir plates on the pond liner, on which I then pour 12 cm of concrete. The current outer walls are partly wood and brick. On the inside of the outer wall there is rockwool + hardboard. But that's really old. So I will strip it all. Will place new rockwool --> then place the pond liner there. Then one layer drywall. That's the outer wall. Then comes the space in between --> there comes rock wool. The the inner construction: A wooden framework with 2 layers of drywall on top, green glue in between. That's the basic idea. For ventilation: a friend of mine came with the idea to let two pipes go through the floor, under the wall and will come up on the outside. That way I can determine afterwards what kind of HVAC or the like I want. One of 1500 euros, or something much simpler. And you are not bothered by the noise. BUT; the problem is that you have to make a hole in the pond liner... maybe you can fix this with waterproof tape or foil, but I doubt it... Maybe then better to put 2 pipes through the walls with an s-duct on the outside. Then you can still put the HVAC/ventilation outside the structure... I'm not sure if I made myself clear, my English is not perfect and I don't have pictures here. So if you have questions, please shoot. I know the plan isn't perfect, but I'm trying to the best with the budget and place I have... If you guys have tips, improvements, please let me know!!

Hi Kingrat, How are you getting on with your build? BTW, did you check with your local authority about regulations for wall cavity ventilation in your area? I notice you decided your brick wall was able to be used as your outer leaf. Did you check that it was fully sealed? Also you need to check that the mortar joints are all good and don't need repointing. Your wall design seems like you intend to use an impermeable barrier on the inside and the outside of your wall, whilst using a timber frame internal wall. Are you sure this is common on your area? This doesn't sound right. If outside is more often damp and cold then it is dry and hot you would usually need to vent condensation from the cavity outwards, so you wouldn't be able to paint your bricks, as they would need to "breathe". Also your idea about running pipes below your floor of in your wall has a problem. It will trash your isolation. Wherever you cut a hole you need to replace the isolation. In ventilation you do this with silencer boxes. It's not practical to have a silencer box on the floor where you need to walk! Also you won't really be able to lay a pipe in advance without knowing the duct sizes you require for your room. Although you are considering which type of HVAC to get, don't forget the V part is not optional! You need to breathe, so you need some kind of ventilation in there the moment the building is used. You have a fully sealed room, there is no passive ventilation. You need to remove the CO2 and bring fresh air into the room. Give us an update when you get time :) Dan

Hi Dan, Thanks for you reply!

How are you getting on with your build?

The project is slowly moving, but it's moving:) Plan is still pretty open. I have only done some preliminary work; digging and stripping the inside of the outer walls. Next step is to poor concrete. I know approximately how I want to do this: First level the soil, then lay pond liner, then 10 cm of insulation (pir plates), then the concrete. The pond liner will protrude at least one meter on all sides. It comes either somewhere in the outside wall, or in the space between the inside and outside wall. Regarding the pouring of concrete: I do not yet know exactly how I am going to do that. Since no concrete truck with a hose can come here. Almost two cubic meters of concrete needed in total. A lot of work with a concrete mixer ...

BTW, did you check with your local authority about regulations for wall cavity ventilation in your area?

A request lays with the municipality, not sure yet.

Your wall design seems like you intend to use an impermeable barrier on the inside and the outside of your wall, whilst using a timber frame internal wall. Are you sure this is common on your area? This doesn't sound right.

I'm not sure if this is common. What's strange about this? Maybe I didn't explain well enough: The outer walls consists of stone, with a kind of wooden window in it (40% stone, 60% wood). On the inside I want to fill the area where wood is, with aerated concrete or other material (similar to the density of oak, where the support beams are made of). And then place drywall on the entire inside. On 4 places I want to make a vent, so there's ventilation in the space between the two walls --> I already bought a few silencer vents (second hand) Maybe it's also an idea to place (gypsum +) OSB board (edited, I said 'hardboard by mistake) on the outside of the outer walls. to make sure it's all airtight + to add mass.

Also you need to check that the mortar joints are all good and don't need repointing.

Will do. Any tips? About the HVAC: you're right and the plans are changed. We will create an in and an out in the walls, with silencer boxes. An idea is to first put one or two of these in: https://www.siegenia.com/nl/products/co ... rs/aeropac (can buy them pretty cheap second hand). And if the ventilation isn't enough or it gets cold or hot easily, I can still put a HVAC unit on the outside (covered) Thanks for your repl(y)(ies) in advance!

Another question: Which foil do I use for the inner and outer walls? For outer: vapor-open or vapor-permeable? For inner: Vapor-proof foil, Vapor-proof foil or Self-regulating vapor-foil? Brief summary of the wall construction: Current outer walls are part brick, part wood. Plan is to put OSB on the outside + gypsum on the inside. Inner walls: 2 layers of gypsum with green glue in between

kingrat wrote:

I'm not sure if this is common. What's strange about this? Maybe I didn't explain well enough: The outer walls consists of stone, with a kind of wooden window in it (40% stone, 60% wood). On the inside I want to fill the area where wood is, with aerated concrete or other material (similar to the density of oak, where the support beams are made of). And then place drywall on the entire inside. On 4 places I want to make a vent, so there's ventilation in the space between the two walls --> I already bought a few silencer vents (second hand) Maybe it's also an idea to place (gypsum +) OSB board (edited, I said 'hardboard by mistake) on the outside of the outer walls. to make sure it's all airtight + to add mass.

In the UK you generally would have to have a vapour permeable exterior surface of a cavity wall to prevent condensation buildup within the cavity and to remove moisture in the wall when it was constructed. So if you have an unvented cavity wall (which you need for any kind of good isolation), you would still require a way for the moisture to escape the wall. In the UK outside is generally colder than indoors. I believe the Netherlands is more cold and damp than the UK (correct me if I'm wrong). So the cavity vapour would need to be allowed to permeate to the outside. Therefore painting the exterior of your wall, would prevent this. That is why I said you need to speak to your local building control officer to understanding the cavity wall ventilation requirements in your area. It is possible you may not need any vapour permeability in your leaves, if for example, you build it with only materials that are not damaged by condensation (Ie. not timber, but concrete (maybe aerated) blocks inside too). But this is something you really need to discuss with your building officer. I don't know enough about your climate, and I struggled with this myself even in my own climate in the UK. I ended up going for a three leaf design to be safe.

kingrat wrote:

Which foil do I use for the inner and outer walls? For outer: vapor-open or vapor-permeable? For inner: Vapor-proof foil, Vapor-proof foil or Self-regulating vapor-foil? Brief summary of the wall construction: Current outer walls are part brick, part wood. Plan is to put OSB on the outside + gypsum on the inside. Inner walls: 2 layers of gypsum with green glue in between

See above. This is entirely dependent on your climate and local building regulations. In the UK the exterior would be wrapped in vapour permeable membrane (breather membrane) and the inside with vapour impermeable membrane. But if you are using a brick exterior leaf where would you put the outer membrane anyway? Brick skins don't usually require a membrane because they are in themselves semi vapour permeable (unless they're painted). If you aren't able to get advice from the local building control officer, then I probably wouldn't paint the outside of the building at all, and then put an impermeable membrane on the inside of the room underneath your plasterboard. But don't quote me on that! :lol: As long as your exterior bricks are well pointed (Ie. the cement between the bricks is not damaged/has holes in it) then you should be OK when it comes to isolation without the paint. Dan

Hi everyone, That was a long time ago... Unfortunately I had a lot of other things to do. But since a few weeks I'm back on top of it. Current status: I've dug 40 cm in the ground, put PVC foil + Pir isolation plates (finished with pur) in there. All sits very nice. Construction steel mats are present. Now, before poring the concrete, I need to do these things: - Make a drawing/design of the whole plan. Among other things, to know where the inner walls will be. So I know where to place the pins / attachment points, on where I can put the wooden construction; - Route power cables through a PVC pipe, which rises up into the concrete floor; - The same idea with the ventilation. A pipe for in, a pipe for out. Through the ground, through the concrete, up to the inner space. About the ventilation. There will be an active in, and een passive out. What's important about the placement? Does it matter that the in and out are next to each other in the inner room? Or should the in for example be in one corner, and the out in another corner? Other suggestions, remarks? Thanks in advance!

- The same idea with the ventilation. A pipe for in, a pipe for out. Through the ground, through the concrete, up to the inner space.

How big are these ventilation pipes going be? Sorry if this has all been covered above.

About the ventilation. There will be an active in, and een passive out. What's important about the placement? Does it matter that the in and out are next to each other in the inner room? Or should the in for example be in one corner, and the out in another corner?

Your supply and return should be as far as away from one another as possible. Greg

How big are these ventilation pipes going be? Sorry if this has all been covered above.

Not determined this yet. Any advice? Something like this for in the concrete --> https://www.gamma.nl/assortiment/renson ... /p/B121418 And then something like this: https://www.gamma.nl/assortiment/renson ... /p/B121379

Your supply and return should be as far as away from one another as possible.

Okay, that's clear. And does the height also matter? For example the in as low as possible and the out as high as possible?

Hi everyone, I made a few calculations and these two scenarios are the extremes; 11,94 m2 vs 12,66 m2 3-4 dB difference in TL on significant frequencies. But, if I understand correctly 10 dB is, for the human ear, a doubling or halving of the loudness. And 3 dB = pretty insignificant... What btw isn't calculated --> that the complete gap = filled with insulation. And the gap is 157 mm in the 11,94 scenario. So, then maybe it is significant What do you guys think?

I'd kill for an extra 3dB of isolation on my project! If it won't cost you much extra financially, I would do it. But, you have to decide what is more important to you - more isolation or more space. Greg

Okay, that's a clear answer, it is valuable thus, the extra 3 dB isolation:) Then I'll have to think... 0,72 extra m2 doesn't sound like much, but it is 6% extra space...

Hi everyone, A big step has been made! Last weekend we've poured the concrete. And it went really well. Before pouring the concrete we made sure that: - there is a ventilation in + out --> through the ground, halfway the isolation and then up through the concrete. So we don't have to make holes in the walls; - power cable through the ventilation pipe (so we also don't have to make a hole in the wall for that) - Outside we will build two s-boxes for the vent pipes Now time for the next part --> making the inside of the outer walls 'soundproof' (before building the room within the room) Right now I'm looking at the possibilities of spraying plaster or concrete... Maybe easier than build a wooden framework with plasterboard on it (something like this is needed, because it isn't possible to put plasterboard right away on the inside of the outer walls). Does someone has experience with this?

kingrat wrote:

Hi everyone, A big step has been made! Last weekend we've poured the concrete. And it went really well. Before pouring the concrete we made sure that: - there is a ventilation in + out --> through the ground, halfway the isolation and then up through the concrete. So we don't have to make holes in the walls; - power cable through the ventilation pipe (so we also don't have to make a hole in the wall for that) - Outside we will build two s-boxes for the vent pipes Now time for the next part --> making the inside of the outer walls 'soundproof' (before building the room within the room) Right now I'm looking at the possibilities of spraying plaster or concrete... Maybe easier than build a wooden framework with plasterboard on it (something like this is needed, because it isn't possible to put plasterboard right away on the inside of the outer walls). Does someone has experience with this?

Why is it not possible to put plasterboard right away on the inside of the outer walls? Paul

Hi Paul, thanks for your reply. The inside of the outer walls and roof are a bit a mess... As in: weird corners, beams, posts. See here a few pictures, so you can judge for yourself: https://imgshare.io/image/Nvr8RZ https://imgshare.io/image/NvrXgc https://imgshare.io/image/NvrIq6 I was thinking about something like this: https://www.youtube.com/watch?v=x9F4fjv ... e=youtu.be Of course it's possible to build a wooden frame work + place plasterboard on that. But I thought this was maybe easier + the current outer wall = the same layer of mass when you spray concrete on it. So you get the max out of the present mass

kingrat wrote:

Hi Paul, thanks for your reply. The inside of the outer walls and roof are a bit a mess... As in: weird corners, beams, posts. See here a few pictures, so you can judge for yourself: https://imgshare.io/image/Nvr8RZ https://imgshare.io/image/NvrXgc https://imgshare.io/image/NvrIq6 I was thinking about something like this: https://www.youtube.com/watch?v=x9F4fjv ... e=youtu.be Of course it's possible to build a wooden frame work + place plasterboard on that. But I thought this was maybe easier + the current outer wall = the same layer of mass when you spray concrete on it. So you get the max out of the present mass

I understand. so the part of the walls which are timber do not have anything behind them? Just the timber framing and panels? and that sits on top and in between the brick? You could use the stucco spray, it might be quite messy and not sure how well it adhere to the wooden panels over time. You could also beef up between the studs by cutting plywood/OSB/Drywall/Cement board (or whatever) so that it fits inside each bay. That's a lot of cutting though. I think if you have budget it would be better to just take out the timber and build up the walls with more bricks, or concrete blocks, tying them into the existing bottom walls and pillars. That would guarantee almost identical surface density and would be a lot more effective than the other methods. Paul

I understand. so the part of the walls which are timber do not have anything behind them? Just the timber framing and panels? and that sits on top and in between the brick?

Yes indeed... Quite an interesting structure...

I think if you have budget it would be better to just take out the timber and build up the walls with more bricks, or concrete blocks, tying them into the existing bottom walls and pillars.

Also thought about that indeed. But the roof isn't from concrete, so is it useful to do this?

kingrat wrote:

I understand. so the part of the walls which are timber do not have anything behind them? Just the timber framing and panels? and that sits on top and in between the brick?

Yes indeed... Quite an interesting structure...

I think if you have budget it would be better to just take out the timber and build up the walls with more bricks, or concrete blocks, tying them into the existing bottom walls and pillars.

Also thought about that indeed. But the roof isn't from concrete, so is it useful to do this?

Well if you decide to use bricks there, and if your new inner leaf ceiling is going to be below the ceiling joists then that means your air gap between the inner and outer leaves at the ceiling/roof will be much larger than the air gap between your walls. The larger air gap will make up for the lesser mass on your roof. Have you already sorted out how to do your roof ventilation without compromising your isolation? If you don't want to add bricks then you can just beef up between the studs where your wooden panels are with drywall. You might want to use a breather membrane on there first before you put the drywall up tight against the wooden panels. Paul

Well if you decide to use bricks there, and if your new inner leaf ceiling is going to be below the ceiling joists then that means your air gap between the inner and outer leaves at the ceiling/roof will be much larger than the air gap between your walls. The larger air gap will make up for the lesser mass on your roof.

Yes, that's the plan. Build the inner leaf below the ceiling joists. We will put them a bit higher, to gain space, but the air gap will still be much larger than the gap between the walls. We will reconsider bricks... Not to bad of an option. But, as you can see, we need a lot of bricks then! Also for replacing the glass sliding door (which is already removed). I see I didn't share a picture of this yet, only of the three other sides: https://imgshare.io/image/20201012-124553.NmuphO

Have you already sorted out how to do your roof ventilation without compromising your isolation?

What do you mean with specific roof ventilation? In the inner room are two vent pipes, in and out. They go through the concrete below the ground, next to the studio I will build two s-boxes, where the vent pipes come up. With the in --> there will be ventilator or maybe later a hvac unit.

You might want to use a breather membrane on there first before you put the drywall up tight against the wooden panels.

And where would you put the breather membrane? Behind the drywall?

kingrat wrote:

Well if you decide to use bricks there, and if your new inner leaf ceiling is going to be below the ceiling joists then that means your air gap between the inner and outer leaves at the ceiling/roof will be much larger than the air gap between your walls. The larger air gap will make up for the lesser mass on your roof.

Yes, that's the plan. Build the inner leaf below the ceiling joists. We will put them a bit higher, to gain space, but the air gap will still be much larger than the gap between the walls. We will reconsider bricks... Not to bad of an option. But, as you can see, we need a lot of bricks then! Also for replacing the glass sliding door (which is already removed). I see I didn't share a picture of this yet, only of the three other sides: https://imgshare.io/image/20201012-124553.NmuphO

Have you already sorted out how to do your roof ventilation without compromising your isolation?

What do you mean with specific roof ventilation? In the inner room are two vent pipes, in and out. They go through the concrete below the ground, next to the studio I will build two s-boxes, where the vent pipes come up. With the in --> there will be ventilator or maybe later a hvac unit.

You might want to use a breather membrane on there first before you put the drywall up tight against the wooden panels.

And where would you put the breather membrane? Behind the drywall?

The underside of the roof deck must be ventilated unless you have a warm roof design. A warm roof design is where you have thick, rigid insulation on the outside, on top of the roof, usually covered by a rubber water proof membrane or metal zinc sheets. If you do not have that, then you have a cold roof design and it must be ventilated properly to avoid interstitial condensation building up on the under side of your roof deck causing rot, mould and water to drip down inside your room, destroying everything. This ventilation has nothing to do with your fresh air supply & return. It ventilation for your structure, so it can breathe. This type of ventilation requires roof vents; usually soffit vents at the eaves and a ridge vent all the way along the top. Of course, this means cutting lots of holes, which would trash your sound isolation, unless designed properly. What you will need to do is put drywall/plywood/osb on the bottom of your roof rafters/joists, leaving at least a 50mm air gap behind it so that air can come into every bay under your roof deck, and then out again at the ridge/opposite side (in the case of a flat roof). The air must have a completely unobstructed pathway. It will look a little something like this: For your other question: The breather membrane would go between your existing wooden cladding and the drywall/plywood/osb that you're going to add. The point of it is to protect your walls just in case your cladding lets water through. It needs to be breathable so that any water vapour that does get through, or any vapour from the interior of the space can escape and not get trapped. So, the membrane is water proof but vapour permeable. Something like tyvek, or any breathable house wrap will work. You must install it properly, overlapping it correctly and sealing it with tape in the right places. Paul

Good point... Thanks a lot for this and the clear description and solution direction. Really appreciate that. Would it also work if we put two vent-boxes (s-style) in the outer walls (opposite sides)? To create an airflow. Regarding the roof --> that there is already quite a big air gap. Very much true... Hadn't thought about it like that. Will save us a lot of work if we just put drywall on the wooden walls. Maybe do the finishing with the concrete spray idea mentioned above. To make sure all corners etc. are both air tight and have enough mass

Is anyone familiar with Tecsound? Never heard of it until now. Could this be a replacement for green glue? Or use together? Or useless at all? Edit: use together ain't too smart I think, since both GG and tecsound have similar functions. And I cannot find any test results from them used together...