Converting Cinder Block Barn To Woodshop

[Karl Juelch]

My wife and I recently purchased a home with a dilapidated 24x32 cinderblock barn on the property. The floor is earth. The exterior is vinyl siding but it is in very bad condition and will have to be replaced.

The plan is to excavate some of the earth to create enough room to pour a cement slab, then line the interior of the building with 2x4 stud walls for sprayed foam insulation, wiring, and sheet rock. I would like to heat and cool with a mini-split if possible.

The property is in a VERY quiet neighborhood, but it is a large lot and the barn is about 60 feet from the nearest neighbor. I will be using power tools most of time, including a 5hp air compressor and air tools, routers, TS, DC, etc, etc. I really do not want to tick off the neighbors, so I have been reading a lot about sound attenuation strategies in the archives. Does anyone have any experience with working in a cinderblock building fitted with sprayed foam insulated sheetrock walls? Does the cinder block have any sound deadening properties on its own, or will I have to go the more thorough route using sound board, mass loaded vinyl, etc?

Thank you for your thoughts, suggestions, criticisms.

Karl

[Brian W Smith]

Karl,block walls suffer from water intrusion coming in the top.I've made good money replacing block lintels,in situ.The water gets in them,and the rebar rusts,then they sort of do a slow motion explode.Check ALL moisture issues.Find the lowest point/elevation on the foundation,and go over every sq inch all the way to the top,following the grade.If it isn't near perfect condition,ask yourself,why.

Proper HVAC maintains just about any environ.......best of luck with your decisions,BW.

[Jim Andrew]

Any kind of concrete does deaden noise. If the walls are in good shape sounds like you did well. Does the barn have a loft for storage?

[Scott Brandstetter]

Karl
Congrats to you and your wife on the new home. I hate moving but love the feeling once it's done. In regards to your shop, once done, you will have a nice area to work in. Reading your post made me remember something I was told quite a while ago. I never looked into it so please don't take it as Gospel.

At one point I looked into moving into a condo (thank the Good Lord I didn't). It was a two story that shared a wall with the neighbor next door. I asked the developer what the sound issue may be and what he does to control me, or them, bothering each other. He immediately responded that he puts a double layer of sheetrock on each adjoining wall. Again, not sure its true that it does much but he did seem confident.

Good luck with your shop and keep us updated with pictures.

[Joe A Faulkner]

I converted a cinder block two car garage to a workshop. I wanted insulation more for maintaining shop temperature than controlling sound. I first attached 3/4 inch firing strips to the block, followed by 3/4" rigid foam. This created a dead air space between the block and foam. Then I framed up traditional 2x4 walls and insulated with batted insulation and went with 1/2" sheet rock on the walls. The building sits 50' from the house. In the summer if I run the router table at night with shop windows open, my wife can hear it but she has never complained that it disturbed sleep. I heat the shop with two 1500 watt electric oil filled radiator style heaters. The building is 22x22. I maintain the temp at about 40 degrees FAR when not in use and bump it up to 55 - 60 when I'm spending time in the shop.

I highly recommend sky lights. I put in three 44" lights on the north facing slope. I regret not placing two or three in the south facing slope as well. Natural light is a big plus in my book.

[Ray Newman]

You may have already thought of this, but insulate the slab. Consider installing a wood floor over the concrete. Your back, knees, and dropped tools will thank you. Also install more than minimum amount of insulation. It will keep the ever increasing energy costs down and soon will repay the extra expense with a warmer/cooler and more shop year round shop.

[Jim Andrew]

#2 on the under slab insulation. Use closed cell foam, like the blue dow board, or the pink foamular. And I agree with the wood floor over the slab. My slab is not insulated under, and I plan to put wood strips down, with foam between and cover with some t&g flooring. Thinking 19.2 centers. Look at your tape, the marks are there.

[Karl Juelch]

Brian, thanks very much for pointing out the possibility for water damage. I spent some quality time today in the barn (quality if you like the smell of ancient horse manure!) checking out the blocks, fittings, etc with a flash light. I am relieved and impressed--everything appears to be rock solid. No evidence of water issues at all. No cracks or any evidence of settling either. Despite its dilapidated condition, the barn looks like it was very well built.

[Karl Juelch]

Any kind of concrete does deaden noise. If the walls are in good shape sounds like you did well. Does the barn have a loft for storage?

Yes, the walls are in very good shape. I inspected them carefully today and was surprised by how good they look.

The barn does have a generous loft for storage, but since the walls are only 8 feet tall, I am willing to lose some loft space in exchange for a higher ceiling. I am planning to reposition the cross ties to give me at least 10 foot ceilings.

[Karl Juelch]

I converted a cinder block two car garage to a workshop. I wanted insulation more for maintaining shop temperature than controlling sound. I first attached 3/4 inch firing strips to the block, followed by 3/4" rigid foam. This created a dead air space between the block and foam. Then I framed up traditional 2x4 walls and insulated with batted insulation and went with 1/2" sheet rock on the walls. The building sits 50' from the house. In the summer if I run the router table at night with shop windows open, my wife can hear it but she has never complained that it disturbed sleep. I heat the shop with two 1500 watt electric oil filled radiator style heaters. The building is 22x22. I maintain the temp at about 40 degrees FAR when not in use and bump it up to 55 - 60 when I'm spending time in the shop.

I highly recommend sky lights. I put in three 44" lights on the north facing slope. I regret not placing two or three in the south facing slope as well. Natural light is a big plus in my book.

Hi Joe. Thanks for sharing your experience with cinder block building conversion. Sounds like a good strategy for insulating the walls, and it probably helped with sound deadening too. I will keep that in mind when I start my conversion--probably still some months off, as we are still working on finishing up the house renovations.

[Karl Juelch]

Karl
Congrats to you and your wife on the new home. I hate moving but love the feeling once it's done. In regards to your shop, once done, you will have a nice area to work in. Reading your post made me remember something I was told quite a while ago. I never looked into it so please don't take it as Gospel.

At one point I looked into moving into a condo (thank the Good Lord I didn't). It was a two story that shared a wall with the neighbor next door. I asked the developer what the sound issue may be and what he does to control me, or them, bothering each other. He immediately responded that he puts a double layer of sheetrock on each adjoining wall. Again, not sure its true that it does much but he did seem confident.

Good luck with your shop and keep us updated with pictures.

Thank you Scott!

From what I've been seeing in the archives, it does appear that double sheet rock alone will have some sound deadening value, and the mass of the cinder block also has some sound absorbing capability, so maybe I will be alriahgt without having to do too much extensive (and expensive!) sound proofing work).

Thanks for the well wishes! Pix to follow.

[Karl Juelch]

Thank you Ray and Jim!

Yes, I am definitely going to insulate that slab. I don't want to spend any more for heating and cooling than I have to!

I have read a lot of threads in the forum archives about putting down a wood floor over the concrete and this is something I would also like to do.

[Mike Heidrick]

Since you are putting in a slab and extruded polystyrene foam, are you considering adding pex for radiant floor heat? Even if you don't do the boiler now at least get the pex in before the pour?

[Jim Andrew]

Don't understand your term crossties. Usually a barn has a floor system above the ceiling, used to store hay in the old days. I see some old barns locally that would make fantastic shops, other than the 8' ceilings. Only way I can see to raise the ceiling on these would be to dig some dirt out before putting in a floor.

[Karl Juelch]

Don't understand your term crossties. Usually a barn has a floor system above the ceiling, used to store hay in the old days. I see some old barns locally that would make fantastic shops, other than the 8' ceilings. Only way I can see to raise the ceiling on these would be to dig some dirt out before putting in a floor.

I'm not a builder so I'm sure I used the wrong terminology. "Ceiling joists" perhaps? The barn has a loft that extends for the entire length and width of the building. Having higher ceilings is more important to me than having a usable loft, so the plan is to tie the roof rafters together with "cross ties" or "ceiling joists" that are maybe 2 or 3 feet higher than the loft floor. They will keep the 2 halves of the peaked roof from spreading, then we can cut away the structure that makes up the loft, leaving me with higher ceilings for the shop.

This "barn" is not one of those beautiful old timber framed structures--I would never consider butchering one of those. Rather, it is a cinder block building that was built in 1971, fitted with an overhead garage door on one end, and 3 horse stalls down one side. I'll post some pictures as soon as I can figure out how to do that on here.

[Karl Juelch]

Here are some pictures. The first one shows the back of the barn. The whole structure was clad in vinyl, but we had to cannibalize some of it to replace damaged siding on the house.

http://i142.photobucket.com/albums/r81/kj262/Barn%20To%20Woodshop/BarnBack_zps816442b1.jpg (http://s142.photobucket.com/user/kj262/media/Barn%20To%20Woodshop/BarnBack_zps816442b1.jpg.html)

The next 2 pictures show the left and right sides of the interior:

http://i142.photobucket.com/albums/r81/kj262/Barn%20To%20Woodshop/BarnInterior_zpsf2215ebf.jpg (http://s142.photobucket.com/user/kj262/media/Barn%20To%20Woodshop/BarnInterior_zpsf2215ebf.jpg.html)

http://i142.photobucket.com/albums/r81/kj262/Barn%20To%20Woodshop/BarnStalls_zpsb825de48.jpg (http://s142.photobucket.com/user/kj262/media/Barn%20To%20Woodshop/BarnStalls_zpsb825de48.jpg.html)

As you can see, there is a lot of work to be done to convert it into a useful woodshop, but I believe there is a great workshop hidden under all that old horse manure!

[Jim Andrew]

My shop looked worse when I started to change it to a workshop. So it is possible. Raising the ceiling will be a sizable chore. Is there flooring on top of the ceiling boards? And are the boards spliced over the beam and wall down the center?

[James Conrad]

Hi Karl,

My suggestions below, most should meet code for your region, wasn't sure if you were planning on pulling a permit.

For your slab isolate it from the wall footings/CMU walls by installing 2 feet of 2" XPS rigid foam down into the ground, it would extend above the ground to the extent of your slab final height. Also, if you are planning on having the slab as your finished floor surface install compression rated XPS rigid foam under the slab at least 2" Foamular 250 is typical but your flatwork guy might have other thoughts. While the XPS will act as a vapor retarder(VR) for your floor, I would suggest a continuous 6mil reinforced VR material in addition, as the XPS can get damaged during concrete install. If you are going with a just a wood floor, you can also install the 2" of XPS on top of the slab instead of under, in this case VR under the slab. Again, use a compression rated XPS 25psi should be sufficient unless you have some really large machines, the blue sheets have that rating or use the Foamular product. Adhere the XPS down to the slab with construction adhesive, tape the seams and you can lay Advantech T&G subfloor material directly on top, 3/4" would be fine but you can get it up to 1 1/8" thick. There is no need for sleepers with this material or screwing it down. Advantech is very stable and is the only material I suggest doing this with, the stuff that looks similar from the box stores will turn into a potato chip at the very hint of moisture. If you plan on putting a flooring material over the Advantech, then you will need to screw it down. With the above suggestions you greatly reduce the slab acting as giant heat sink or a point of moisture intrusion.

Walls, for your spray foam application, install your 2x4 framing with a 1-2" gap from the exterior CMU wall. Use a closed cell spray foam and fill the space to the front of framing. This will act as your VR, isolate your framing from the exterior walls, meet energy code, and address your noise concern greatly. The spray foam, or any plastic insulation, needs to be covered with a product that has a 15 minute fire rating. 1/2" sheetrock or 5/8 exterior rated plywood meets that requirement, the sheetrock needs to be taped and mudded. Not sure around you, but around here spray foam applications are very expensive depending on thickness $8-15 a square foot. If cost is a concern, you can use 2" of XPS adhered to the walls and seam taped (acts as your VR), then your wall framing filled with a high density fiberglass or Roxul insulation would be my suggestions.

I don't see any major issues with raising your ties/ceiling joists other than it would only be good for light storage. The ties would need to be in the lower 1/3 of the roof height. However, you may run into issues with length of span using conventional lumber, 2x10 or 2x12 typically only come in lengths over 20' to max of maybe 28' with doug fir, as I am not sure which dimension you are spanning. If the 22' span, then by raising the height you reduce the span length it is possible to make it a continuos span with conventional lumber, 2x8 doug fir can be had in longer lengths and would be good as filling this space with closed cell spray foam will meet energy code, not sure what your existing roof rafters size is... I have thoughts on making this more usable space, but after raising the ceiling it might not be worth doing. Consulting with a structural engineer is a good idea here and will be required if you are pulling a permit.

By raising the ceiling you also provide for the potential of more windows in the space between the top of the wall and your ceiling on your gable ends. Extended along the length on both ends of that space would add a great deal of natural light as all I can see for window potential are those 3 stall doors, or you can bust holes in the CMU walls with is not much fun. Since gable ends typically are not load bearing, framing should be easy to modify.

Exterior wise, be sure to plug the gaps between your furring strips at the bottom to stop bugs from making a home behind the siding and block off the gap at the top if its open to your inside framing, blocking maybe accomplished with your spray foam, if you can use a pressure treated stop and spray foam I think thats better, some bugs do enjoy living in some spray foams, mice too. Also, from the pics it looks like there are no roof vents? The easiest to install would be gable end vents, unless you want to cut the ridge vent in and install soffit vents.

Yes on the mini-split, a 18-24k btu heat pump unit will heat and cool the space quite nicely.

I am sure there is something I am over looking, but thats my suggestions at a first pass.

[Karl Juelch]

My shop looked worse when I started to change it to a workshop. So it is possible. Raising the ceiling will be a sizable chore. Is there flooring on top of the ceiling boards? And are the boards spliced over the beam and wall down the center?

The ceiling boards also function as the loft flooring. The ceiling joists are 2 piece, butted together over the center beam/wall. I figure the new joists used to raise the ceiling height will have to be installed first, then the loft, beam and wall can be dismantled.

[Karl Juelch]

Howdy James,

Thanks for your very comprehensive reply. It's going to take a while to digest all that. You bring up some good points I had not thought of.

[Mike Heidrick]

While you are digesting, start searching for used XPS (extruded poly styrene - blue from lowes or pink foamular from menards and HD) 25psi like suggested. With the right deals on craigslist and/or buys from roof deinstalls and such you will say a TON of money vs buying it used. I am doing 1.5" as that is what I found used local but search for 2". 80+ sheets of it gets expensive for me.

[Michael N Taylor]

I have been involved with block buildings for 42 years and any good foam company can drill small holes in the block and fill the cavities with foam. There are two types of foam, closed cell and open cell with the closed cell giving a higher R factor and being water, mold and mildew proof. The open cell is less expensive and does a good job of insulation but is not water, mold and mildew proof. Either one will work for what you need and eliminate the framed walls and the drywall if you install the electrical on the block surface.
We have core filled many block was in commercial construction this way with excellent results.

[James Conrad]

I have been involved with block buildings for 42 years and any good foam company can drill small holes in the block and fill the cavities with foam. There are two types of foam, closed cell and open cell with the closed cell giving a higher R factor and being water, mold and mildew proof. The open cell is less expensive and does a good job of insulation but is not water, mold and mildew proof. Either one will work for what you need and eliminate the framed walls and the drywall if you install the electrical on the block surface.
We have core filled many block was in commercial construction this way with excellent results.

The caveat here would be they insulate the exterior of the building with a layer of continuos rigid insulation to reduce the thermal bridging, at least that is how it is done in New England.

[Jim Andrew]

I'm sure filling the cores would help overall, but the concrete part of the wall would still be uninsulated. And the R value of the block material is practically nothing. So putting a continuous panel of foam on the inside, and framing with 2x4's and insulation is a pretty good way to go. Although you will lose a little space on the inside of your building. I think I would put the foam up first, then frame the walls, it is pretty hard to work the foam in behind your framing. If you use glue, be sure to ask your supplier for the glue that does NOT dissolve the foam. Regular construction adhesive WILL dissolve the foam. I have tried it, I know.

[John Densmore]

Look into Sound Transmission Class, here is a wiki with a bit of information. http://en.wikipedia.org/wiki/Sound_transmission_class There are better articles out there describing different construction plans.

[Karl Juelch]

Thank you all for your suggestions, comments, etc. I will post with updates as they happen.

[Chris Padilla]

Another thought in regards to sound isolation is to frame with 2x6 sill and top plates and 2x4 studs staggering the studs such that one set touches the cinder block and the other does not. The "does not" group gets the sheet rock. Then fill 'er up with spray foam...should be VERY NICE for sound AND temperature control.

[Karl Juelch]

Another thought in regards to sound isolation is to frame with 2x6 sill and top plates and 2x4 studs staggering the studs such that one set touches the cinder block and the other does not. The "does not" group gets the sheet rock. Then fill 'er up with spray foam...should be VERY NICE for sound AND temperature control.

I'm guessing the studs supporting the sheetrock should be on 16" centers? Then what about the studs at the cinderblock wall? 16" centers too? Like building 2 walls right next to each other. Interesting idea. Sounds expensive but probably also very effective?

[Karl Juelch]

Look into Sound Transmission Class, here is a wiki with a bit of information. http://en.wikipedia.org/wiki/Sound_transmission_class There are better articles out there describing different construction plans.

Excellent link! Thank you.

[James Conrad]

I'm guessing the studs supporting the sheetrock should be on 16" centers? Then what about the studs at the cinderblock wall? 16" centers too? Like building 2 walls right next to each other. Interesting idea. Sounds expensive but probably also very effective?

While this is a method used in more conventional stick built framing, when a cement structure is involved you really don't want wood touching a surface that can transmit temperature and moisture easily. In the case of a CMU structure like this, framing 16oc with a gap between the wall and framing with the use of a spray foam or rigid barrier serves the purpose without the added fuss and cost of offset framing. Since the wall is not load bearing you could use 19.2 or even 24oc depending on your wall covering.

[Mike Olson]

All the sound isolation threads I have read always suggest the same basic thing. Room within a room.

If you are going to put up stud walls to insulate then your half way there. Just make sure that the studs you put up do not come into direct contact with the block wall. Don't screw, nail or glue them to the cinder block. Attach them to the floor and ceiling and that's it. There is also a tube of sound proofing glue/calk that you can apply to the studs before you put up the drywall or OSB.

[Joe Bradshaw]

Karl, You have a nice project ahead for sure. My plan would be to completely gut the interior, paying attention to any load bearing supports. Then pour your floor as recommended in previous posts. Then you can run some tools inside and have some one listen to them outside. Sound attenuation is good, but, if you don't need it, why pay for it. I can bearly hear my 5 HP compressor that is in an un-insulated barn when Iam on my porch. It's about 100 feet from my barn to my house. Good luck with your project.
Joe

[Karl Juelch]

Karl, You have a nice project ahead for sure. My plan would be to completely gut the interior, paying attention to any load bearing supports. Then pour your floor as recommended in previous posts. Then you can run some tools inside and have some one listen to them outside. Sound attenuation is good, but, if you don't need it, why pay for it. I can bearly hear my 5 HP compressor that is in an un-insulated barn when Iam on my porch. It's about 100 feet from my barn to my house. Good luck with your project.
Joe

You make a very good point!

[Karl Juelch]

I've dug into the archives here and followed up links posted on this thread to outside information on soundproofing. There always seems to be a lot of emphasis placed on sound coming through the walls, but not so much on ceilings. Is it because the sound is directed upwards, that makes it not as important, or is it just assumed that what goes for the walls also goes for the ceilings?

I'd also like to take this opportunity to thank everyone who has responded to this thread--you all have given me a lot of food for thought and I greatly appreciate it!

Karl