Lyndhurst Garden House

Lyndhurst Garden House
Lyndhurst Garden House

Friday, January 20, 2012

Grout Color

Skipping past all the stressful days from early December to today, Jan 20...

On Wednesday Jan 18 I went to the Windsor Home Depot nearest my home and purchased the porcelain tile I had actually picked out at a Evers store near work several months ago.  (It was coincidental that I had to go home over my dinner break.  Normally I like to purchase stuff where I pick it out, and I like the Evers store where I picked it out, so I would have bought the tile there if I could have.  Contractors generally like to pick up from store nearest my home, so this was better for them.)  I was feeling a little guilty about not buying at the other store, but the salesperson at the Windsor store was very helpful.  She helped me pick out the Flexbond adhesive which is top notch.  She also helped me pick out the polyblend grout color that seemed to match the tile most nicely.  I noticed quite a few of the tile boxes seemed to have been mishandled, but she assured me that there would be enough good tiles in their stock to meet my needs.

The next day the Supervisor texted me that lots of tiles were cracked, so he had gotten home depot to provide an extra two boxes, their last ones.  I had fears that I would be seeing lots of cracked tiles...

However on Thursday night I observed tile, and it looked perfect.  Under dim light, it converted the workshop from rough garage to palace.  I noticed that they had centered the tile in the room, so that the center grout line goes right down the middle of the room, and in between the two french doors.  Of course that also meant there were cut tiles around all the sides, and that they could get the most use of cracked or chipped tiles.  But anyway, it was probably the nicer way to do the installation.  I was feeling good.  Grout had not yet been installed.

Today (Friday) the grout was installed.  When I observed the situation a few hours later, I was horrified.  Instead of the nice match between tile and grout, the grout looked grey and irregular, and stood out clearly from the tile.

Now I see this is a common problem with polyblend grouts.  There are various tricks and treatments to correct it.  Here is a good discussion.   Here's one colored Grout Sealer available in colors to match all different colored grouts.  Otherwise, most grout companies make colored grout sealers to match their own colored grout colors.  Custom Building Products (maker of my Polyblend grout) makes at least two kinds: Grout Renew and Aquamix, the latter being a water based low-VOC formulation.   The Home Depot here only carries Grout Renew and only carries it in a few colors...though that does include the Haystack color my grout was supposed to be.  Now I'm thinking I want a slightly darker/richer color.  The display of my chosen tile (Brazilian Slate) is grouted with Fawn #156.  In the store that looks slightly richer (more saturated) and slightly darker than Haystack.  But under my kitchen light, Haystack looks darker.

Here's a list of other colored grout sealers:

Enrich N Seal
Mapei (Mocha is said to be nice on top of Haystack)
C-Cure
DuPont Stone Tec Professional

Another trick is suggested: wash with 50% vinegar in water solution to clean and remove hard water deposits which add white cast.

There appear to be as many as 4 boxes of tile left over, so having enough good tiles does not look like it was actually a problem.  (Update: On Sunday night I returned 3 apparently unopened boxes of tile.  A fourth box was opened, so I checked each of those tiles out carefully and kept 7 perfect ones as spares, one was cracked and got returned to Home Depot along with the 3 unopened boxes.  Credit was about $25 per box.  I also got credit on one unopened bag of Flex Bond.  Another bag left by contractor had holes in it and I decided to have contractor dispose of that when they were cleaning up.  The tilers had only apparently needed 2 bags of Flex Bond, and left about 1/8 bag or more in each of those two.  The spec by Custom is 90-100sqft for one bag so that would be 1.65 bags for 165 square feet.)

Now the contractor wants the second to the last payment of $2000.  The last payment would be about $1500.  This is making me very uncomfortable, considering all the unfinished work and remaining issues:

1) Interior trim (window, baseboard, AC, french doors*).
2) Install and seal around AC.
3) Exterior trim around french doors.
4) Exterior paint and caulk touch up (at least one very thin seam in back).
5) Shelves including large 30" deep shelf in back.
6) Clean up of site, including stuff left by current contractor, and previous contractor.  The previous contractor left intimidatingly large pieces of scrap concrete, including one right next to slab, slab forms still in place, and long and short pieces of rebar, including #6 rebar.  It was agreed and specified in contract that all this stuff would be removed.*  The current contractor has left scads of stuff related to tile installation, sheetrock, and bags of scraped foam.

(*The price shown in contract for removing concrete spoils, forms, and rebar left by previous contractor is $275. Somehow I don't think I could get the job done for anything close to that.  Maybe $750, or more.  This would require work like demolition work, breaking apart huge mounds of concrete, but done carefully, so as not to disturb slab.  It's not a job for junk busters.  That has always made me nervous.  Anyway, since this is a fixed price contract, in theory the contractor is supposed to get the job done regardless of how much it ultimately costs them.  But contractors are notorious for either finding ways to shift excess costs onto homeowner or leave work undone or done in substandard way.  This happened during the spray foaming, though I'm basically satisfied with how that ultimately worked out, I payed a mere $635 extra for a dual-foam approach which seems fine to me in principle, though it could have been argued I should have gotten a refund instead of paying more for it, since I was filling in the walls with mostly cheaper open cell foam.  As I've said before, this makes me understand why DoD has been known for using Cost-Plus contracts, so as not to be subject to inferior products or work, though at a high price.)

Thursday, January 19, 2012

The Housewrap was Accepted (sigh)

After much thought and research, I decided to accept the housewrap installation done on a rainy December 10th just before the hardi siding was slapped on.  I made this decision during the following week.  Since that time, I've been mostly too exhausted dealing with that and subsequent issues to keep up with the blog, so this post is just the beginning of an attempt to catch up.

Recap: instead of the #30 felt for housewrap I specified after much research online, Lowe's plastic housewrap was used.  Seeing this going on, I called the supervisor twice.  Finally, on the north side and the corner of the east side, felt was installed OVER the Lowe's housewrap.  I'm not sure what happened on the west side, it may have had the felt also, or just in the corner like the east side.  I never got a chance to see it before it got covered with siding (and more about the siding issues later).

As disappointed as I was with the Lowe's housewrap, which wasn't what I had specified in the interest of 75 year building longevity (my dream, etc), at least it was code legal and probably satisfactory to most building inspectors.

It was the use of felt on top of the plastic seemed like it might be especially problematic.  Sure, two housewraps would almost certainly shield the house from external water better than one.  But the issue, still an unknown, is whether the use of felt on top of plastic might trap any water that happened to get through both housewraps, ultimately leading to damage to the sheathing and framing.


My best guess is that since both housewraps are water vapor permeable, this won't happen.  So, at least I can hope it won't be a problem.

Actually, sometimes limited amounts of felt are required to be put on top of a plastic housewrap for certain reasons.  For example, with Hardiplank, one option for the butt end joints is to put extra flashing behind them and on top of the actual plastic housewrap.  In this case, the "flashing" is either a special kind of plastic made specially for this purpose by Tyvek, or felt.

Famous "building scientist" Lstiburek doesn't think housewraps are the big deal they are made out to be.  They do some good, he says, and it is AFAIK that he has used Tyvek on his own house, but he says that in almost all cases, wall failures are not related to lack of housewrap or the particular housewrap but due to other building errors, such as failures to properly flash windows.  Housewrap cannot fix other problems, and it most cases it does very little.  If you have a serious water leak, housewrap is not going to fix it.  On the other hand houses got by for centuries without modern housewraps.  Housewraps simply reduce moisture intrusion a little bit over time.  They may tend to help mask tiny building errors but won't do anything for the big errors.  Basically, water shouldn't be getting into walls, and there should be no reason for significant amounts of vapor to escape from walls either, especially from the sheathing outward.

Now one issue wrt the potential water trapping of the two housewraps I have on some parts of my workshop is how the vapor permeabilities of the two different materials add up.  My first frightening though that they might multiply.  For example, if one material had permeability of 0.05 and the other 0.15, the resulting permeability if this were true would be 0.05 * 0.15 or 0.0075.  At that point we've gone from "vapor permeable" to "not significantly vapor permeable."

Thinking about this a lot, I decided that it's much more likely that the resulting permeability of a series of permeable layers is determined roughly by the least permeable layer.  So if either one was good enough, the two in combination will be good enough also.  One obvious example of this is where the same kind of housewrap is overlapped at seams.

Now regardless of whether this was a big issue or not, I had the contractor in my hands on this one.  The felt housewrap was clearly spelled out in the contract, and they recognized that mistakes had been made, and said they were willing to do it all over again to my satisfaction.  But I decided not to have them do this.  Why?

Because I decided that tearing down the siding and housewrap and putting up felt and new siding would leave me with sheathing and framing full of small nail holes.  Now that the sheathing and siding has nail holes in it, guess what, the housewrap better be done right the second time, or moisture would slowly enter through those holes and ultimately eat the structure apart.

Now of course this is done all the time during re-siding.  One can only hope that during re-siding, the housewrap and such is done correctly.  In my case, I'd have the same crew that screwed up doing the re-installation, and they'd probably make other mistakes, along with being angry about it.

I suggested that they also tear down the sheathing and framing and then do the construction, but the builder dismissed that out-of-hand, and I suspected I wouldn't be able to get them to do that even with threat of lawsuit.

There is an inherent virtue in the original construction.  Even if it's not perfect, it's better than reconstruction, unless the reconstruction is done much better, and there is no guarantee of that.  In fact, not only is there no guarantee, I could be virtually certain it wouldn't be done correctly the second time either.  Even if only felt were installed, since these guys don't like felt much, it is almost certain they would not do single-layer felt correctly.  And some people say if felt is used, a dual layer of felt should be used.  And others say that #30 felt paper for housewrap isn't what it used to be.

I also had concerns about the siding installation.  But after talking them over with the supervisor, I decided it was all OK if not exactly as I would have wanted it.  That will be the subject of a future catch-up posting.

In any case, that was the decision I made during the heat of the battle in December, and it's far too late to go back now.

The Lowe's brand housewrap is obviously a perforated reinforced plastic housewrap.  I can see why the installers like this, in addition to being the cheapest available it's also the easiest to install.  They just staple it on.  Tyvek has to be carefully taped with Tyvek tape, something that requires a special skill.  Tyvek cannot be stapled because that would make it fracture and tear apart.  One might worry for this and similar reasons that Tyvek might not hold up well over time, either, an in fact there are reports of old Tyvek having fallen apart over time.  The great virtue of Tyvek is that it has very high vapor permeability

Some online research suggested that Lowe's housewrap is actually rebadged Pactiv Classic wrap, which used to be sold as Amowrap name.  It is tear resistant and has a permeability of 15.  That's acceptible, if no where near as high as Tyvek.  Tyvek has a moisture vapor permeance of 58, the highest of any housewrap I know about.

Felt paper, when dry has a lower permeability of about 5, which is a typical code minimum.  But it rises to 30 if the felt actually gets wet.  (Actually, I'm a bit confused between Grade D building paper and #15 and #30 felt, and I'm not sure what my builder actually used, but they all have permeance around 5-8 when dry.)

So the combination of the two housewraps would be expected to have a variable permeability from about 5 to 15.  OK, if perhaps much less than optimal.  The thicker felt layer might allow actual water to drain away more quickly, though, than the perfwrap by itself pressed up against the hardi siding.  The low end of the permeance is actually determined by the felt, so possibly I'm not that much worse off than if only felt had been used.

If, on the other hand, the two wraps are incompatible and eat each other apart, the worst that could happen is that it would be like having no housewrap.  But that would actually have the advantage of greater permeance.

Another thought is that mistakes like this happen all the time.  Buildings are, in climates like mine, quite forgiving.  Lots of mistakes can be made, and a building will still go without serious problems for decades.  I'd probably get decades of use out of a building constructed only with plywood, like my sheathing.  I have truly lousy Masonite hardboard on my actual 28 year old house.  Parts of it in the front (where there was water spash) deteriorated and had to be replaced.  But the rest of it is actually still holding together with the original 28 year old paint applied by the cheapest tract home builder in San Antonio (Rayco) which no longer exists.










Sunday, January 8, 2012

Spray Foam Insulation...ready for the big time?

By all accounts, Spray Foam Insulation has the best available insulation properties of any material still in use.*  As well as having good to excellent R value (open cell foam is about the same as fiberglass, closed cell even better), it completely seals a structure from air leaks (closed cell goes further and also seals against vapor and moisture), and remains dimensionally stable over the life of a building (fiberglass batts typically compress over time, reducing their effectiveness, and loose fill insulation settles).  The effect of air leakage hasn't been fully incorporated into standard analysis (R value) which focuses on radiant energy but is clearly very important.

(*Asbestos may have been even better, but has been illegal since the 1970's for public health reasons.)

But despite that, spray foam insulation is not widely used in the large tract home developments I have seen.  Residentally, spray foam is mostly used only in custom construction or remodeling.  And I'm beginning to think that may be a good thing.  While a finished structure with cured insulation is safe for the inhabitants (unless it catches fire) it is not clear to me that sufficient care is always taken to protect spray foam installation installers, and this would likely be even worse with large scale use.  And a major fire in a housing tract where spray foam insulation without fire retardant is used would be a very bad thing (not easy for residents to escape from fumes all around).  And the chemicals used to provide flame retardancy may be actually the most toxic of all for the installers, so that's not necessarily the answer either.

To create spray foam, an isocyanate (usually MDI) is mixed with a polyol, usually in the spray gun itself.  On application, the spray foam is not fully cured, and as a result there are free isocynates in the initial polyurethane foam as well as free isocynates relased from the applicator itself.  It takes several days for the foam to fully cure, during which time additional isocyanates are released.  The polyols are generally not considered as harmful. though they may actually be responsible for most of the smell.  Isocynate is odorless until it reaches very high concentrations normally not seen.

The key health hazard from isocynate is asthma.  Insufficiently protected installers can develop increasing sensitivity to MDI (which is a respiratory irritant) first leading to temporary asthma, then permanent asthma.   If they continue working with MDI after developing permanent asthma, a severe deadly asthma attack could develop.  Unfortunately, when different lines of work are hard to find and especially with the same level of pay, workers may indeed continue working with MDI, covering up their symptoms in various ways.  Here is an account of one worker in the auto refinishing business who persisted in working with isocynate based polyurethane car finishes after doctors warned him not to, and wound up dead.  Isocynate is an essential ingredient in polyurethane of all kinds, though sometimes polyurethane finishes are pre-mixed and considered more safe than those created by mixing the two ingredients on site.  The MDI used in spray foam insulation may be somewhat less toxic than isocynates used in creating other polyurethanes such as those used in two-part finishing products.

Here's is an official report from the State of California about isocynates which echoes the same story.

Now it's true that as a limited and elite industry, with workers required to have training and so on, the hazards of spray foam installation are taken more seriously than hazards in other areas of construction.  For example, all workers who work with cementious and clay siding products and fiberglass insulation should wear particulate filter respirators, but I did not see that done when my building was being built, and I suspect that is all too common.  On the other hand, you will almost always see spray foam installers wearing full body suits with full face respirators.   Unfortunately, sometimes the installers and assistant installers who do the foam scraping afterwards might not.  The extra health precautions often demanded by law for use with spray foam installation are part of the reason for the high price for spray foam insulation.*  But even with an elevated level of protection, it may not be enough.  For example, spray foam installation is best done with supplied air, not respirator filters.  And respirators should not be the first line of defense: the first line of defense should be proper airflow through the workspace.

*Or at least the high price, and limited availability, of spray foam insulation is justified by health concerns, whether or not fully safe methods are used.  The installing company may simply pocket the extra money without putting much into increased safety.

One can only imagine there would be far more occupational asthma and death from spray foam application if it was used in all residential construction as a matter of course.  At least until the safety issues are taken as seriously as they should be.

An additional issue is that subsequent contractors may be exposed to excess isocyanates if the next stage of construction, typically sheetrock installation, isn't delayed for a few days to allow the foam to cure.  In my case, that became part of the plan anyway by coincidence (I have jury duty starting on the Monday after the Saturday foaming), but in the rush-rush residental tract construction business, that delay would probably not happen.

*****

Knowing all this now, I'm not sure I would have specified my insulation.

What I did specify was closed cell foam applied to the full 5.5 inch width of all 2x6 framing, later ammended in a verbal agreement to covering all the rafter supports.  That seemed to me to be the best way to get the maximum energy efficiency possible, and it seemed to be accepted by the general contractor (though the actual contract is vague, the contractor agreed to what I said in an email).

But when the day actually came, the general contractor said all that foam that was unnecessary, and that all the foamers would do would be to apply 1.5 inches of closed cell foam to the walls and 2 inches under the roof deck.  No more was necessary, it would just be wasted.

Well I knew immediately this was wrong and inadequate, and further research backed it up.  Under the roof deck, in particular, local and international residential code specifies R30.  That would require over 4 inches of R6.8 closed cell foam installation, not merely 2.  Also, the R value increases linearly with thickness, and the DOE actually recommends R30 - R60 for residential construction in Zone 2 where I live.

But then the contractor offered me to augment the initial 1.5 and 2 inches of closed cell foam with the cheaper, lighter, and easier to apply open cell foam, up to the full width of the framing as I had wanted, for a mere $1100 extra.  Doing that with closed cell foam would require an additional $3000.

I did some research to confirm that this was OK.  In fact, a number of building consultants have written about this dual-foam approach, one called it an inexpensive way of getting the best benefits of foam, one called it "the best of both worlds" (you get the water vapor sealing of closed cell with the acoustical aborbing properties of open cell), and a major building advisor has said it is OK but he couldn't imagine how it would be cheaper than all closed cell for logistical reasons, thinking different equipment, truck, and crew would be needed, so why not go all the way with the full thickness of the superior thermal insulating properties of closed cell foam?  But he was wrong about that last part, apparently now many foam systems can handle both kinds of foam, switching from one to the other with a mere purging of the hose, and the chemical systems are compatible.

(I'm ommitting here the saga of the two days of spray foam installation, that is a long an torturous story that deserves a separate post.  Actually, the saga continued the next week, as the contractor tried to pass on an additional price increase, and I fought back, and we came to a reasonable settlement.  In the end, I paid only a $635 extra for the 0.5 pound foam on top of the 2 pound foam...though it could be argued I should have paid nothing extra and got the full 5.5 inches of more expensive closed cell I thought had been agreed to.)

The actual spray foams used by my installer, South Texas Insulation, were both made by Gaco Western, apparently one of the biggest names in spray foam you've likely never heard of (you have probably already heard of names such as Dow, BASF, and other major spray foam manufacturers).  The closed cell foam is Gaco Western 183M (the website says 183 but I believe what they used was actually 183M as the description fits better) and the open cell foam is Gaco Green 052.  I inspected the closed cell foam after installation and it is yellow and very hard (the installer pounded on it to show how hard) and the open cell foam was blue and rather flimsy, especially at first.  When inspecting the open cell foam part of the installation, I noticed that the western part of the ceiling looked a little thin.  The installer said that was where he switched foams, and initially that section got a mixture of closed and open cell foams (I'm not sure if that is good!) and because of the high closed cell content, it would actually insulate better than the thicker layer of pure open cell found elsewhere.  The color is also slightly off in that section, a strange yellowish blue (but not green).  I'm wondering if that is correct installation, it might seem that the lines to the spray gun should have been fully flushed when switching from one foam type to the other.  That may represent a kind of installation error, and installation errors are often claimed to be the source of long lasting outgassing problems (while correct installation is said to have outgassing that disappears quickly enough not to be a health issue for subsequent workers or occupants).

Initially, during my inspection soon after foaming and scraping was complete, and a few hours later, the smell was very intense and annoying.  I didn't get any eye watering, chest tightness, or similar allergic issues from brief moments (less than a minute) spent inside.  But even with a healthy breeze and the french doors wide open and the A/C opening uncovered, the smell was intense and annoying.  I smelled it on my shirt later, and decided to wash all clothing that had been worn during my brief moments inside.  I continued the process of washing clothing afterwards on each visit, even washing my two down jackets.  I even had "flashbacks" of smelling the smell with nothing that could have picked it up around me.  I had one brief flashback this morning, in my bedroom, two weeks later.

It was about week later before the sheetrock was installed.  During that week, the smell did go down considerably, and lost the especially annoying quality.  It was still noticeable, though not physically unpleasant, by day of sheetrock installation.  I left the french doors and A/C opening open as much as possible.  I had to close or cover them on Monday January 9th because of rain, but it was only for about 24 hours.  During that time there were two warm days which reached temperatures in the mid 70's, several very cold days, and one hard freeze to 28 degrees.  I figured the warm days and even the hard freeze were good to vent or squeeze all the more toxic chemicals out.

Immediately after the sheetrock was installed, there was no noticeable spray foam smell, or perhaps it was masked by the very strong smell of sheetrock dust.

I'm thinking and hoping now that the 6 days of delay from installation until the application of sheetrock were very fortunate, and I have pre-outgassed all of the really bad stuff so it won't be seeping out slowly from the sheetrock henceforth.  I notice that some building codes require 3 days from spray foaming to sheetrock installation.  One brand of spray foam, Icynene, claims that sheetrock can be installed within minutes of foaming.  I'm wondering if that kind of installation practice explains the issue that one guy had with his dream home project, being forced to sell it because he couldn't move in.

Of course, I don't yet know what the smell will be like after the building is completed, the A/C unit installed, and the french doors left closed for days at a time.  If there is a long term continuing problem, I have found a solution which which would be far cheaper than tearing the whole building down and starting over (since it is nearly impossible to remove spray foam, especially the hard cell kind, from a finished structure).  I could get a $699 VOC filter with 28 pound carbon filter.  Such a filter is said to be able to handle VOC problems for up to 2000 sq ft.  On low speed fan, it would consume about 28 watts.  It might be good to have such a unit to take care of outgassing from the old equipment I plan to store in the building as well.

It may be likely that the highly reactive and volatile Isocynates are long since gone, either they have reacted with other chemicals or materials or simply vented away.  What remains is the residual odor from unreacted Polyols, or other chemicals used, such as the flame retardant.  Historically, fire retardants have been among the most environmentally hazardous materials used in polyurethane foam.  PBDE's had long been used in all kinds of polyurethane foams as flame retardants, they are now banned in many areas.  Humans are now found to contain significant amounts of PDBE's, and this is one reason they have been banned, but this is generally believed to be mostly from eating fish and animals that have been absorbing surplus PBDE's found in the environment as opposed to inhalation from bedding or building materials.

Here is a brochure that says Gaco Western does not use PBDE's in their Gaco Green Foam.  But they don't say what fire retardants they do use.  Icynene goes farther and says they don't contain any brominated compounds.  But one never knows if whatever it is they do use may simply be the 'next' banned chemical that caused serious problems.

I have a theory as to why even the relatively less toxic polyols (often derived from vegetable oils) used in spray foam could cause allergic problems.  Conditioning.  If someone has been exposed to the Isocynate/Polyol outgas mixture, it is initially the Isocynate which causes severe reaction.  Except in very high concentration, the Isocynates are odorless.  What may happen, however, is that operant conditioning either at nervous system level or immune system level associates the polyol smell with the isocynate reacting, so even much later the polyol smell might trigger allergic reactions.