John Sayers' Recording Studio Design Forum Archive

That looks awesome!!!!!

Greg

Here's some pics of the ceiling soffits I built. They're full of light fluffy for bass trapping and will be covered with fabric and some down lights will be installed. They're about 2' wide and 1' 6 high at the front and about 1' at the back.

Gregwor wrote:That looks awesome!!!!!

Greg

Thank-you Greg, it's nice to hear!

And here's the pics of the rough framing for the windows.

Theres 3 windows at the front of the control room. The frames here are for the cutouts while the glass itself will be in the speaker soffit and side wing framing, forming my RFZ.

The main central window will look into the large tracking room, the front left window will look into a smaller booth and the the front right will look out into nature.

Hi guys,

Has anyone got any tips for ray tracing 2 angles at once? I'm trying to use sketch up to ray trace reflections from monitors to some windows on side walls which are angled both horizontally and vertically, not only is it time consuming but also very confusing...

Any help appreciated!
Paul

I've found this useful: Create the surface upright (not angled) and save it as a component, then rotate it with the rotation tool. Then when you edit the component the axes are set to the local space instead of world space.
So exit your component, draw a line from your monitors to the face of your window. Now edit the window component and draw a short line from the intersection point on the surface straight forwards (the surface normal), it will be one of the local axes.
Now exit the component.
Using the protractor tool, click on the intersection point on the surface, set it to measure from the surface normal line, measure the angle to the monitor line but don't click, just look at the angle at the bottom of the window and remember it, then measure the opposite direction and type the figure you remembered, click to set a guide. Now draw your reflection along the guide.

I've written this from bed, without a pc, so I may have missed some steps, but have a go!

Dan

Waka wrote:I've found this useful: Create the surface upright (not angled) and save it as a component, then rotate it with the rotation tool. Then when you edit the component the axes are set to the local space instead of world space.
So exit your component, draw a line from your monitors to the face of your window. Now edit the window component and draw a short line from the intersection point on the surface straight forwards (the surface normal), it will be one of the local axes.
Now exit the component.
Using the protractor tool, click on the intersection point on the surface, set it to measure from the surface normal line, measure the angle to the monitor line but don't click, just look at the angle at the bottom of the window and remember it, then measure the opposite direction and type the figure you remembered, click to set a guide. Now draw your reflection along the guide.

I've written this from bed, without a pc, so I may have missed some steps, but have a go!

Dan

Thanks Dan, I'll try that out!

Paul

If I get time, I'll try to make a quick video of how I do it. It is fast and pretty easy if I remember correctly!

Greg

Gregwor wrote:If I get time, I'll try to make a quick video of how I do it. It is fast and pretty easy if I remember correctly!

Greg

Thanks Greg, that would be amazingly helpful

Guys, I am having a bit of a stressful time right now after discovering what I thought was a leak in the roof!

Sorry for the long read, but please read it all if you dare so that you can offer me some advice.

The white residue in the photos is actually where the water has mixed with the caulk and dripped all over the place.

But, the plot thickens...

1. Where this supposed leak was found the framing and roof deck behind the insulation is wet and there is black mould on the surface. The insulation is obviously wet as well.

2. Now, in other places all the way along the ceiling there is what looks to be condensation on the inner face of the insulation, but behind it both the insulation and roof deck is bone dry.

So... what is happening here?

Have a look at the diagram I've attached of my roof/ceiling construction. Remember, this is the INNER INSIDE OUT leaf of the control room and I am building the outer leaf around this at a later stage. Therefore there are NO VENTS in the ridge or the soffits as this is my inner leaf.

Now, the leak if there was one I am not too worried about as I can easily fix it. I am more concerned with the presence of condensation...

If all of this damage was caused by condensation and there actually in fact was never a leak from the outside, then where the hell is all of that moisture coming from???

It cannot be from my breath/sweat as I am not in there enough to warrant this happening, and even if it was the door is always wide open while I am working in there.

My theory is either it must be coming from the outside air, or the concrete slab that is still drying out???

It was really cold up until recently, it's only been the last week or so where we've had fairly hot weather....
Perhaps the moisture is rising up to the ceiling during the colder nights, and then in the day time when the sun is on the roof it's heating it up and then the moisture is trying to fall down into the room again???

One thing I know for sure is that there was no condensation or moisture anywhere before I installed all of the insulation and the hangers. I triple checked it and left it for a good few weeks of rain before installing insulation just to be sure. Now with all of that insulation butted up against the roof deck and the hangers beneath it is just acting like a sponge on the inner surface. It is mainly condensing on the face of the insulation which is directly BEHIND the hangers (in the peak of the ceiling).

Of course, if I had already built the outer leaf with my roof on top of it then either I would have a vented "third" leaf, or I would just make it a warm roof which does away with the need to have vents. As I cannot currently do that what do you think I should do???

Right now I have just opened both doors and will get a fan in there to dry it all out the best I can, but I do not think it will be a permanent fix...

If I had my silencer boxes and ventilation system installed in there do you think this will irradicate the problem???

What I am trying to understand is how other people who have inside out ceilings (presumably sealed airtight like mine) with insulation in the bays do not also have this problem? Is it because they have an insulated cavity behind their ceiling with an outer leaf and roof etc? And because I only have the one leaf which is dividing the inner room with the outside world it is causing a problem?

Thanks for taking the time to read and any advice would be much appreciated

Hi Paulus, it most definitely looks like a condensation problem.

When you added all that insulation you significantly increased the thermal performance in your roof.

The problem you have is the air stays warm up until it meets the OSB roof deck, then it rests against it (if there is a vapour barrier) or begins to absorb. As it does this the cold roof deck cools the vapour, and it condenses... All over the roof.

The confusing thing is you say the roof deck is dry. That is probably just gravity drawing the water through the insulation and leaving it on the lower surface of the insulation.

Having a completely sealed room like this allows a surprising amount of water vapour to remain in the room.
I would think a ventilation system would help it, but really you need your AC in there as soon as you can.
If you add silencer boxes and just have passive ventilation it will help alot.

I don't think the concrete drying is the problem. How long has it been laid?

When you get your second (outer) leaf on and a vapour barrier between the two, against your inner osb3, it will significantly help.

How did you water proof your roof deck, on the other hand though?

Dan

Waka wrote:Hi Paulus, it most definitely looks like a condensation problem.

When you added all that insulation you significantly increased the thermal performance in your roof.

The problem you have is the air stays warm up until it meets the OSB roof deck, then it rests against it (if there is a vapour barrier) or begins to absorb. As it does this the cold roof deck cools the vapour, and it condenses... All over the roof.

The confusing thing is you say the roof deck is dry. That is probably just gravity drawing the water through the insulation and leaving it on the lower surface of the insulation.

Having a completely sealed room like this allows a surprising amount of water vapour to remain in the room.
I would think a ventilation system would help it, but really you need your AC in there as soon as you can.
If you add silencer boxes and just have passive ventilation it will help alot.

I don't think the concrete drying is the problem. How long has it been laid?

When you get your second (outer) leaf on and a vapour barrier between the two, against your inner osb3, it will significantly help.

How did you water proof your roof deck, on the other hand though?

Dan

Thanks Dan...

The weird thing is where I thought I found a leak it is soaking wet behind and in front of the insulation, that is only one section in the middle of the ceiling. The rest of it is bone dry behind the insulation.

I left the door open last night and when I came back this morning the condensation on the face of the insulation had got better since yesterday, so it seems like having at least the door open is helping it to dry out.

I water proofed the roof deck with roofing felt, that's it. There is no vapour barrier.

The slab has been laid about 6 months and I've just finished putting the laminate floor down over underlay on top of it.

If I have AC in there then yes, it will keep the air cooler, and if I have ventilation it will pull some of the moisture out via the inline fan, however without the outer leaf, will that be enough to stop the condensation?

Paul

The

Paulus87 wrote:The weird thing is where I thought I found a leak it is soaking wet behind and in front of the insulation, that is only one section in the middle of the ceiling. The rest of it is bone dry behind the insulation.

It's very possible you had a leak. But is that area right at the apex though? If so, it might be the condensation just "pooling" there.

Paulus87 wrote:I water proofed the roof deck with roofing felt, that's it. There is no vapour barrier.

I assume you have some seams? It might be worth getting up there to check them all.

Paulus87 wrote:If I have AC in there then yes, it will keep the air cooler, and if I have ventilation it will pull some of the moisture out via the inline fan, however without the outer leaf, will that be enough to stop the condensation?

I would think so, because it will always be on when you're in the room, and when you're not in the room the vents will add passive ventilation. I can't say for sure though. As you may know, cavity walls were designed to prevent condensation. So a single skin (leaf) wall is always on the back foot really.

Dan

As an alternative temporary measure, you could add exterior thermal insulation to your roof deck (celotex or something similar) and put felt on top of that. So you would have a warm roof then. As your roof is almost always the biggest problem, this might be good enough in the mean time. Then when you build your outer leaf, just move the celotex to the outer roof deck.

If you do this, follow the correct warm-roof design for your area (not sure about wales building regs). You will probably need to replace your felt with a vapour control layer.
Dan

Paul,
Hopefully you do not have a roof leak.

In my studio build back in 07 it was very airtight. By the time I had put new lumber (wet), drywall and mud and paint. I ran a dehumidifier for a couple weeks and took out 20 gallons of water. If I would have known this before hand I would have stated drying out earlier. I ran into a problem with moisture building up between the panes of glass. That is when I knew I had a problem.

Typical construction usually does a dry out period before and after drywall. Like you have found out, just by leaving the doors open, it is helping. If you can, run heat/propane and fans to help remove the moisture.

Hopefully it is that simple and like I said hopefully not a roofing problem.
Best
T