Building Home Studio - concept plan reveiled - feedback?

[kingrat]

Thanks guys. I'm convinced now I need an HVAC system. I just have to find relative cheap way to do this.

In the next few weeks I will make a financial oversight. We'll know what to do:

- Digging, pour concrete
- Bricklaying & making roof airtight
- Build room-within-a-room: wooden studs with rockwool attached to outer wall. Air in between. wooden studs with rockwool - gypsum + green glue + gypsum
- 2 doors: plain doors, mass added & rubber strips.
- HVAC system placed above the inner room. Pointed roof, so enough space. In/out in inner + outer wall. On outside of outer wall silencer boxes
- Fixing power: if there's not enough watts, fix it. If there's interference, fix it.

That's about it, roughly... Sound easy, but I know better...

[Waka]

Thanks guys. I'm convinced now I need an HVAC system. I just have to find relative cheap way to do this.

In the next few weeks I will make a financial oversight. We'll know what to do:

- Digging, pour concrete
- Bricklaying & making roof airtight
- Build room-within-a-room: wooden studs with rockwool attached to outer wall. Air in between. wooden studs with rockwool - gypsum + green glue + gypsum
- 2 doors: plain doors, mass added & rubber strips.
- HVAC system placed above the inner room. Pointed roof, so enough space. In/out in inner + outer wall. On outside of outer wall silencer boxes
- Fixing power: if there's not enough watts, fix it. If there's interference, fix it.

That's about it, roughly... Sound easy, but I know better...

Hi kingrat,
You don't need studs attached to your outer brick wall usually. It's there a reason you have those listed?
You can get rockwool that is self supporting and doesn't need a frame to hold it, just stack it up, then build your other frame in front of it.
Also as long as your rockwool isn't too dense you don't want an air gap at all. Research had found that fully filling is best, even fluffy loft insulation works fine inside an MSM wall and doesn't reduce performance.

Dan

[kingrat]

Hi Dan,

I've listed those bricks here because I thought this was needed to keep the rockwool in place. So you would say: just fully fill the space between the inner and outer walls? With not too dense rockwool.

Another question: you need airco/heating/de-moisturize etc. in the studio --> but doesn't the space in between the walls doesn't get moist? And if so, how can you prevent this?

[Waka]

Hi Dan,

I've listed those bricks here because I thought this was needed to keep the rockwool in place. So you would say: just fully fill the space between the inner and outer walls? With not too dense rockwool.

Another question: you need airco/heating/de-moisturize etc. in the studio --> but doesn't the space in between the walls doesn't get moist? And if so, how can you prevent this?

Not sure I follow your point about the bricks, but yes just fully fill any cavity in your wall with light insulation.

You definitely need to find out how cavity wall moisture is controlled in your area. If the only options acceptable to building regulations in your part of the world are to ventilate your cavity then you will need to build 3 leaf walls. But there are some alternatives.

You can look here for ideas:
https://www.buildingscience.com/documen ... r-barriers

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.

Dan

[kingrat]

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?

[Waka]

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

[kingrat]

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?

[Waka]

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

[kingrat]

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...

[kingrat]

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!!

[Waka]

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

[kingrat]

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!

[kingrat]

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

[Waka]

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.

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!

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

[kingrat]

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!