Stage Floor Replacement

[VeeDubTDI]

Well, it's finally finally happening. We're getting a new floor to replace our worn out, 19 year old, heavily used tongue and groove floor.

The new floor will be two layers of plywood on top of the plywood underlayment that's on top of the sleepers (3 layers total), with the top surface being A grade and painted black.

Here are some pics to feast your eyes upon. Sorry for the crappy cell-phone quality of some of them. Others aren't so bad.

Click to make the images full-size. I'll be posting more as the project progresses.

 

[VeeDubTDI]

As you can see, the pit covers downstage are not getting replaced. They're in good shape, and we will just sand them down and paint them black.

 

[Footer]

No Maso? ???

 

[DaveySimps]

I agree, why not Masonite as a top layer? I just checked my local pricing. I can get 3/4" Masonite cheaper than 3/4" grade A ply. Plus, it is a better surface for theatre in general. Just curious.

~Dave

 

[derekleffew]

It may be too late, but if it were me, I'd get those soft goods off the floor and bagged/wrapped with Visqueen ASAP! I agree that the top surface should not be painted pine plywood. I've only used Masonite in 1/4" and 1/8" thinknesses, and would agree that's a better top layer.

Do you intend to permit screwing on your new stage?

 

[Van]

.....
Do you intend to permit screwing on your new stage?

I'm a huge fan of 1/4" MDF as opposed to Masonite. It tends not to buckle as much. 'Course there's nothing that say you can't always go in and lay a layer of MDF over the top layer of ply as a prophylatic measure.......

 

[derekleffew]

...of 1/4" MDF as opposed to Masonite. ...

What's the difference? Isn't MDF the same as untempered Maso? And while were on the subject, since Masonite no longer manufactures sheet goods, what's the new version actually called? HDF? Should the glossary entry be edited?

Another gem of wisdom that Van previously liked: Prime all six surfaces of any pressed-fiber sheetgood before laying.

 

[SteveB]

'Course there's nothing that say you can't always go in and lay a layer of MDF over the top layer of ply as a prophylatic measure.......

Unless the planned layer is flush with doors, entry way, etc... Not to mention pit limits needing to be reset. Adding even a 1/4" layer sometimes throw's everything off.

Steve B.

 

[MillburyAuditorium]

Congrats on the new stage Ours needs a good sanding To many dance academy's using the wrong tape

Quick question for anyone, How come some theatres paint the stage black? I prefer the glossy brownish look myself. Does it do something to the lighting? Or is it just prefernece?

 

[Van]

What's the difference? Isn't MDF the same as untempered Maso? And while were on the subject, since Masonite no longer manufactures sheet goods, what's the new version actually called? HDF? Should the glossary entry be edited?
....

I'm glad you asked. MDF or Medium Density Fiber board is made of much finer fibers, actually much more like dust. The entire sheet is impregnated with resins then press molded resulting in six sides that have the same smooth texture. When you cut through MDF the new edges have the same dense smooth edges. Masonite or Tempered Hard board is much more of a paper product. The difference in the fibers making up these two similar yet different engineered lumber products is readily evident. Masonite fibers tend to be coarser and are much more loosely packed. Masonite or tempered hardboard comes in two varieties ; single and dual sided tempering. The tempered side is the slick side, you'll notice that the back side of single sided tempered masonite has a weird textured side this is the result of the manufacturing process which is similar to hand made paper, if you've ever done that, the resultant paper has a smooth-ish top and the backside of the paper takes on the texture of the screen.

One of the main reasons I prefer MDF over Hard Board is the uniform distribution of the resins throughout the product. MDF is much more moisture resistant and therefore much less likely to buckle and therefore requires far fewer screws to secure it to a floor. Lastly MDF tends to be more more uniform in thickness than Hardboard While I do prefer MDF it is wise to take several precautions when doing extensive work with it;
The resultant dust is much finer and therefore tends to get everywhere.

There is a MUCH higher Formaldehyde content in MDF and it is strongly recommended that a dust mask or respirator be worn when working it.

MDF, because of it's higher density, can tend to dull blades a little quicker than other engineered lumber products.

MDF tends to give friction burns much more easily than Masonite, be careful when maneuvering a large sheet as simply sliding your hand to reposition your grip can result in painful burns.

 

[VeeDubTDI]

Well, the decision for no Maso was based, in part, on the information from a number of consultants. Ultimately, we think that the plywood will hold up better than the maso in our situation. This space sees a lot of heavy use, and we're trying to keep maintenance to a minimum, even if the surface isn't as nice. Especially with the large number of tap groups that we get, the edges of the maso would start to fray and get soft, making the surface uneven.

At this point, we can't add maso to the top of it because it would change the height of the stage when compared to the concrete off-stage rooms and the backstage hallway. If the plywood ends up not working out very well, we can always change the top layer to maso in the future.

This is a state job, so we're locked into it now. We can make changes in the future, but not right now. So, we'll see how things go.

As for the soft goods, we're replacing all of the legs and teasers in the near future. The project is going out to bid soon. I'm not terribly concerned about them at the moment. If they were new, I would have taken them down and stored them properly.

So all in all, this is a big project that needed doing, and we'll continue to play it by ear. At this point, the current plan is leaps and bounds above what we had before.

 

[VeeDubTDI]

Pics from yesterday and today...



After it's all drying and such, we're going to paint it with "Deck Paint" stage floor paint.

 

[mstaylor]

I will be interested in how the finish looks after staining it with the screw heads being spot patched. I woud think it would be splotchy. It may be better to field patch the playwood and paint it instead of staining it.

 

[VeeDubTDI]

Can't see the patch marks at all. They patched, sanded, stained, patched, sanded, stained, and stained again. The finish looks very even... just the slightest hint of roller marks before it was totally dry, and those were only visible from certain angles. I'll see what it looks like tomorrow.

 

[VeeDubTDI]

pics from today...

 

[teqniqal]

A bit of history: "Back in the day" when Masonite Corporation made tempered pressboard, they used to sell a product called "Duron WR". This was super-dense hardboard product that was Water Repellent. It made great stage flooring. Alas, 'tis no more.

However, Sierra Pine now makes two products that are roughly the same as Duron WR. If you contact them they will send you samples to test for workability (no, you won't get a 4'x8' sheet of wood in the mail...). A bonus is that these are formaldehyde-free products.

The Medite FR product information can be found at:
(http://www.sierrapine.com/index.php?pid=79)

The Medite II product information can be found at:
(http://www.sierrapine.com/index.php?pid=67)

The Medite II is not Fire Retardant, but it is stronger and absorbs less moisture, so it may be a better solution for the abuse that stage flooring receives. To make it more suitable for stage use the Medite II could be treated with an intumescent paint like:
* NoBurn” (http://noburn.com/)
* “FlameStop” (http://www.flamestop.com/)
* “FireFree88” (http://www.firefree.com/ff88.php)
* “PaintToProtect” (http://www.painttoprotect.com/)
* PPG “SpeedHide” (http://corporateportal.ppg.com/NA/PAF/PMC/Brands/FPC/400_Intumescent/)
* Contego “Fire Barrier” (http://www.contegointernational.com/)

We should all be using intumescent paint for anything that comes onto the stage. Depending upon the product, it can come in a color, or be tinted to match a color. Also of interest is the videos on some of these product web sites that show "with" and "without" comparisons of structure burn rates (some with, and some without, accelerants, too.)

One of the reasons generic "masonite" doesn't last too long on a stage floor, and the same reason that soft pine and plywood floors deteriorate rapidly, is because they are not dense enough to withstand the point loads that piano casters, cable crates, and ladders present to the surface.

Generic "masonite" is a soft material technically known as Class 0 Hardboard. This is all they stock at most lumber stores. If you want a tougher product you usually have to special order it. Hardboard is available in 5 Classes (0-4), and it is the class 3 and 4 products that are typically more appropriate for use on stage floors.

A second consideration is the means of attaching the hardboard/MDF to the subflooring. You must countersink the screw holes before you screw the deck down. The high density of the Class 3 or 4 hardboard/MDF doesn't allow it to just mash out of the way like plywood.

Also of great concern is the resilience of the floor with regard to dancers. ESTA has developed recommendations for sprung floors to reduce the likelihood of joint injuries. An unyielding floor is not good. Not that this doesn't mean that the floor is locally spongy, but instead that the floor is monolithically spongy - very much like a Basketball Court floor (and for the same reasons).

 

[derekleffew]

Can't see the patch marks at all. They patched, sanded, stained, patched, sanded, stained, and stained again. ...

I'm curious as to what they used to cover the screwheads. It looks like drywall joint compound, but I'm thinking maybe auto body filler (Bondo)?

 

[TimmyP1955]

I'm glad you asked. MDF or Medium Density Fiber board is made of much finer fibers, actually much more like dust. The entire sheet is impregnated with resins then press molded resulting in six sides that have the same smooth texture. When you cut through MDF the new edges have the same dense smooth edges. Masonite or Tempered Hard board is much more of a paper product. The difference in the fibers making up these two similar yet different engineered lumber products is readily evident. Masonite fibers tend to be coarser and are much more loosely packed. Masonite or tempered hardboard comes in two varieties ; single and dual sided tempering. The tempered side is the slick side, you'll notice that the back side of single sided tempered masonite has a weird textured side this is the result of the manufacturing process which is similar to hand made paper, if you've ever done that, the resultant paper has a smooth-ish top and the backside of the paper takes on the texture of the screen.

One of the main reasons I prefer MDF over Hard Board is the uniform distribution of the resins throughout the product. MDF is much more moisture resistant and therefore much less likely to buckle and therefore requires far fewer screws to secure it to a floor. Lastly MDF tends to be more more uniform in thickness than Hardboard While I do prefer MDF it is wise to take several precautions when doing extensive work with it;
The resultant dust is much finer and therefore tends to get everywhere.

There is a MUCH higher Formaldehyde content in MDF and it is strongly recommended that a dust mask or respirator be worn when working it.

MDF, because of it's higher density, can tend to dull blades a little quicker than other engineered lumber products.

MDF tends to give friction burns much more easily than Masonite, be careful when maneuvering a large sheet as simply sliding your hand to reposition your grip can result in painful burns.

With the materials I've seen, I would have reversed the descriptions. The MDF I have seen, when compromised, will pull apart in layers like cerial box material.

 

[ruinexplorer]

Well, the decision for no Maso was based, in part, on the information from a number of consultants. <snip> Especially with the large number of tap groups that we get, the edges of the maso would start to fray and get soft, making the surface uneven.

Wow, I would have thought that you would have wanted to stay with TnG if you have a large number of tap groups. If they are professionals, they usually prefer hardwood to plywood. Of course, that would have been more expensive.

Personally I hate stages with Maso floors.

 

[DramaTeach]

Resurfacing Stage Floor

Hey Guys!

I work at a public high school near Chicago and have finally convinced folks that we need to do something about our stage floor.

Here's the issue: for years we were unable to paint, drill into, build on the "beautiful" hardwood floor. However, after years of plays being performed on the stage, it was inevitable it would fall into disrepair. Currently the hardwood (I'm not sure what the wood is) is buckling in places. They are going to fix that and replace the front facing of the stage.

Here's part of an e-mail I got today:

What I want to do is put a layer of plywood down over the floor and then install a layer of melamine (like that of most Stages).

My question is: is this going to be the wisest choice for staging top? We do two major productions a year on the stage and then a bunch of band concerts, choir concerts, miscellaneous performances.

Thanks!