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Beachboy
March 20th, 2008, 09:27 AM
PArticule board, MDF, plywood, or marine plywood.

which material would you want as your underlayment to support your granite counter tops in both kitchen & bathrooms? I need to know why you'd use one material over the other too.

I was under the impression the marine plywwod would be the best avenue to take with regard to moisture in the islands.

Do any of you have MDF stories, good or bad with regard to using it as an underlayment?

craigwatanabe
March 20th, 2008, 10:05 AM
PArticule board, MDF, plywood, or marine plywood.

which material would you want as your underlayment to support your granite counter tops in both kitchen & bathrooms? I need to know why you'd use one material over the other too.

I was under the impression the marine plywwod would be the best avenue to take with regard to moisture in the islands.

Do any of you have MDF stories, good or bad with regard to using it as an underlayment?

No way with particule or MDF. At the least use treated plywood. You can go with marine ply but I've seen people use the green hardiboard as an underlayment simply because it's the best suited for that application. Hardiboard is basically cement board with a lot of fiber. Green Hardiboard is used as a backing behind tiles in showers and behind backsplashes in kitchens. It will stand up to water or moisture better than plywood.

You can find green hardiboard in the flooring department at Home Depot.

salmoned
March 20th, 2008, 10:42 AM
Underlayment! What a novel idea, but why? I've always just used a framework as a spacer for the countertop (to achieve the desired height above the cabinets). Are you laying granite tiles?

craigwatanabe
March 20th, 2008, 11:30 AM
Underlayment! What a novel idea, but why? I've always just used a framework as a spacer for the countertop (to achieve the desired height above the cabinets). Are you laying granite tiles?

It's always recommended to use an underlayment for kitchen counters especially something friable as granite for added strength so you don't accidently crack that expensive countertop.

alohatim
March 20th, 2008, 12:11 PM
I agree: Treated plywood. Even though hardiback is waterproof, I don't think it would support weight horizontally like plywood. It is my understanding that the glues used in most plywood these days don't breakdown in water so marine plywood is unnecessary.

Beachboy
March 20th, 2008, 03:01 PM
Underlayment! What a novel idea, but why? I've always just used a framework as a spacer for the countertop (to achieve the desired height above the cabinets). Are you laying granite tiles?

no, granite slabs! What is happening is I'm pissed off with the work at my home. After agent convinces me to upgrade both bathrooms & kitchen with granite slab counters. I find out her builder used MDF for the underlayment!!:eek: This just look like another form of pressboard/particule board to me. I'm worried sick about what moisture is gonna do to it in due time!
Seems to me that having granite counters supported by particule board is defeating the purpose of having quility work.

Composite 2992
March 20th, 2008, 06:29 PM
MDF is pretty dense but is about as water resistant as cardboard.

Plywood is a lot better option. The main difference between conventional plywood and marine grade is that there's no voids in marine grade. Of course the glue used between the plys has better water resistance, too.

However, notice that marine grade ply is never treated. It's to help ensure that polyester fiberglass resin will adhere well. Apparently fiberglass resin generally doesn't adhere well to treated lumber. So while marine grade plywood is definitely more solid, it's also more vulnerable to termites.

So I'd recommend treated plywood. To support the load, plywood works best when oriented edgewise.

Also, whenever carrying stone countertops, always carry them edgewise. I heard of one instance where a slab broke when a supervisor insisted that his worker carry it flat.

cezanne
March 20th, 2008, 09:28 PM
Underlayment! What a novel idea, but why? I've always just used a framework as a spacer for the countertop (to achieve the desired height above the cabinets). Are you laying granite tiles?

I've seen that done with 1x4 frames nailed onto the cabinet tops and I think that's suffice. Sheet underlayment is overkill if you're going with the regular 3/4" granite. Granite is some hard stuff. I'm told that even an overhang of 10 to 12 inches wouldn't need support.

I wouldn't worry about the MDF. If it really bothers you... just paint some varnish underneath.

All of that said... I went with baltic birch-ply for my install. Talk about overkill.:o

craigwatanabe
March 20th, 2008, 10:12 PM
No no no!!! Do not use 1x4's they're too weak for the weight of granite. Even 2x4's can be too weak if laid down flat. You always lay load bearing framework on edge to support heavy loads.

You can go cheap by no underlayment, but in time as framework warps and sags you'll regret it as your granite slab edges separate. You never lay stone or manufactured stonework on anything but a continous flat surface for even weight distribution. Granite is very heavy material and simple framework will not hold up to it over time. At least an underlayment will give that framework stronger sheer strength. Let the underlayment take the stresses of the sagging frame. If you secure granite to an open wood frame and that frame buckles, the granite will crack at the stress points.

And regarding handling large flat friable material, yes always handle it vertically and do not carry it flat. It will bow and crack.

kani-lehua
March 21st, 2008, 10:12 AM
okay. so do the same principles apply to other types of countertops? natural stone (pre-fab granite, marble, limestone, onyx, travertine), solid surfaces (corian, gibraltar, LG hi-macs, staron), quartz composite (silestone, onequartz, zodiaq), richlite, concrete, nevamar, ceramic & porcelain tile or wood?

if the underlayment is meant for support purposes, what does moisture have to do with it if the natural stone countertop is sealed?

Beachboy
March 21st, 2008, 05:08 PM
not sure how that works, but granite counters put off their fair share of moisture from what I understand!

Beachboy
March 21st, 2008, 05:29 PM
One other concern I have with MDF is "out gassing". Shouldn't agents or builders inform buyers when this type of building materials(health hazards) is used on one's new home being constructed? Buyer should definitely have the option when hazardous materials are gonna being used to construct part of their home, right?
I found this about MDF on internet:

"According to most cancer institutes, MDF must be sealed with paint or polyurethane to prevent formaldehyde being released into the air (a process known as out-gassing). This is necessary because formaldehyde contains known carcinogenic (cancer causing) properties."

I'm pretty worried about this!

escondido100
March 21st, 2008, 07:19 PM
aloha.... i am a general contractor in kona..... i actively import pre fab granite counters from china and i work for both lowes and home depot as their cabinetry installer and kitchen remodeler.
Granite: some installers will use nothing as a sub base if the granite is 1 inch or more thick..... the best material when using a subtop is cabinet grade 6 ply ply wood......... the treated stuf is exterior grade and it is hard to get the warpage out of it for this application. the cabinet grade is really stable and flat.....the extra plys add a lot of strength......HD has a maple plywood for 39 to 49 a sheet which is a bargain......they get it in china......this last year i have probably done twenty kitchens with it and have had no problems.....the granite installers love it.....one time when HD was out of the 6 ply i used the 3 ply fir and it was a lot of extra work to get it flat.
NEVER use MDF or particle !!!!! also the green board that was referred to is also not to be used as it is a drywall product and is only moisture resistant and not structural...... i have torn out dozens of old kitchens and PB and MDf are both usually a terrible mess after just a short while.....you would be surprised....... as to the slats that were mentioned.....that is used in preparation of soild surface type counter tops and is usually put in by the installer. ie....corian or silestone or similar products must breath properly and the manufacturer has very specific instructions on the sub surface to be used. hardi backer or wonder board is used as a base for tile installations.....usually used over plywood...glued and screwed......when you go this route you have to think about elevation details and edge treatment.....we tear out a lot of tile over plywood only..... it is easy to demo compared to proper install with hardi backer....... i see a lot of sub standard work here in hawaii.......so many of trhe trades people have come from all over CONUS and all have different ways of doing stuff...... a contractor from arkansa building 80K homes is gonna do it different than a guy from La Jolla where home cost at least 1M or more......and the local folks that learn the trade here are lucky when they learn the right way to do things and seem resistant to change...... my 2 cents....hope it helps.

kani-lehua
March 22nd, 2008, 09:49 AM
i'll have to take this all into consideration when building my next home. i have had no problems with my corian countertops that were purchased through home depot (o'ahu) and installed by superior solid surface. after reading escondido100's post, my conclusion is that the "underlayment" is for structural/support?

Composite 2992
March 22nd, 2008, 10:42 PM
escondido:

So that means building a frame-like support out of ply without a plywood top, and having that structure support the granite or Corian top? That sounds like what I saw done by Solid Surface technologies for a remodel job a while back.

As for plywood, is that 3/4"?

Regarding cabinets, the best I've seen so far is made of 3/4" ply. Often maple or birch. The doors vary a lot but the boxes themselves are almost always ply and never composited particle or MDF.

I'm toying with the idea of making my own cabinets someday. Just learned how to make the doors with the mortise & tenon joints and floating panels. I was lucky and someone gave me the necessary router bits.

I enjoy doing things like this but don't know if I could do it as a job. Besides, which, I'm way too slow!

craigwatanabe
March 22nd, 2008, 10:57 PM
When it comes to sheer strength support you can go down to as thin as 3/8" for walls. For countertop support I'd go 3/4" as it's the thickest ply you can get. When it comes to sheer strength in walls you're looking at the lateral strength so thickness isn't as important as tearability. But in countertops thickness does count as weight can vary, such as a 250-lb carpenter standing on that granite counter with no underlayment or supports too far apart to handle that load.

For granite you can seal it to protect the underlayment. If you're using tiles or non-continuous slabs with grout then you should seal at least the grout annually. For marble countertops sealing is a must as marble is porous.


Escondido100 when you're in the Hilo store come visit me I work at the Hilo 8453 store. You must know John Bey. He does the estimations for our store for price quotes. You may also know Mark Kitagawa of Big Island Countertops who imports granite countertops from China by the container.

cezanne
March 22nd, 2008, 11:02 PM
after reading escondido100's post, my conclusion is that the "underlayment" is for structural/support?

Correct. Thanks for the info Escondido.

craigwatanabe
March 22nd, 2008, 11:11 PM
I'm toying with the idea of making my own cabinets someday. Just learned how to make the doors with the mortise & tenon joints and floating panels. I was lucky and someone gave me the necessary router bits.

I enjoy doing things like this but don't know if I could do it as a job. Besides, which, I'm way too slow!



Whatever you do make sure you have an ample supply of cabinet hinges. I deal with many customers who come into our store asking for direct replacement compound-joint cabinet hinges only to find out that because of the location of the forsner-bit mounting point was proprietary to that particular hinge, they cannot get one of our "Knob Hill" or "Liberty" brand hinges to fit that mount location.

The 6-ply is a 3/4" cabinet grade plywood we sell for I think about $30 (I think) for a 4x8 sheet. It's not treated as Escondido100 indicated.

There is a green hardi-backer board that is sold in the Flooring department (and not in the Building Material department) of HD. This is definately not the drywall or greenboard but is a solid cement-fiber board that weighs a lot more than the greenboard.

In any case I strongly believe using an underlayment is good. It helps strengthen the cabinet the countertop is sitting on as well as strengthen the subsurface for which that countertop is attached to. Remember structural strength is defined by it's frame and not by it's facade. In home building some building codes require the use of sheer walls under the T111 exterior panel facades to hurricane-proof the walls of a home for lateral support.

salmoned
March 23rd, 2008, 12:34 AM
Nuts, if you develop a sagging frame, then you must've gone el-cheapo on your cabinets. I've never seen such a problem, since the framework is always entirely supported by the cabinets.

Beachboy
March 23rd, 2008, 09:20 AM
Nuts, if you develop a sagging frame, then you must've gone el-cheapo on your cabinets. I've never seen such a problem, since the framework is always entirely supported by the cabinets.

who are you talking too? I don't recall saying anything about sagging framework. I started this thread to better understand the plus & minuses of MDF use in Hawaii. To me there doesn't seem to be much difference between particle board & MDF....both are nightmares in my opinion, and now I have my granite counters sitting on top of MDF underlayment!!!

Plus I must worry about my two boys(ages 2 & 9yrs old),and the effects of out gassing from the MFD. The builders never sealed the MFD that was used on my counters!!!

kani-lehua
March 23rd, 2008, 11:11 AM
being that i don't know much about this topic, i'm wondering if the granite slab is somehow adhered to the underlayment or does it just sit on top of it? if it is adhered to the underlayment, would that somehow prevent, "the effects of out gassing from the MDF"? if so, could you then seal the other support areas to prevent the out gassing? is there any way to get the contractor to do it the "correct" way?

WindwardOahuRN
March 23rd, 2008, 12:22 PM
As per the instructions of the granite company from which we purchased our slab kitchen counters we used 3/4" plywood sheets as a base for the countertops. The company installed the countertops so I'm not quite sure whether they used an adhesive or not.
We did the rest of the kitchen ourselves---a true test of the solidity of a marriage :eek:. Both the marriage and the countertops are doing just fine six years later. :D
Another thought---MDF is available in exterior grade. Is it possible that this was the kind of MDF that was used in the counter application? If so, it's supposed to be extremely water resistant. I believe that it's so resistant to the elements that its used for road signs. There is also a low-formaldehyde version of MDF.

escondido100
March 23rd, 2008, 02:47 PM
when installing granite on a plywood sub base i use a high quality polyurethane construction advesive.....you can also use a high quality silcone as an adhesive. as to MDF ...many mdf products have a skin of melamine on one or both sides..... if this is what you have then it would be considered sealed in those areas.... the edges remain unsealed. i rather doubt that an exterrior mdf would have been used in an application such as this since sign board is rather expensive...unless the contractor has adopted this as a technique that he feele is superior to other techniques.....if so that means he has thought this out and would be willing t o explain his logic. and offer a gaurantee for his work beyond the minimal as required by law.
since the granite is extremely stable by itself i would be too worried about the use of MDF ....other than the out gassing and there are different schools of thought on this as well.......i had a client that was allergic to the formaldehyde and when we built a house for them they did a lot of research on products that dont out gas......there are some but it wasnt easy to do..... one of the reasons i got the job is that i was willing to work with them on it......it was alot of extra work.....formaldehyde is in darn near everything..... maybe not so much any more but 15 yrs ago it was.

craigwatanabe
March 23rd, 2008, 09:15 PM
I wouldn't worry too much about the gassing as homes built here in Hawaii are pretty open (meaning not sealed like homes in the mainland). There's lots of cabinets and even those computer desks and entertainment cabinets you by and assemble have some level of MDF. Lots of today's speaker cabinets (your subwoofer in your living room) are made of MDF as well as those sub boxes in cars.

As for countertops, I don't care how sealed it is, once the surface is breached, water can seep in and the damage occurs, that's why I don't like those laminated countertops that have the backsplash and lip that you can buy at home improvement centers (such as Home Depot, Lowes, City Mill) because they're made of particle wood.

craigwatanabe
March 23rd, 2008, 09:19 PM
being that i don't know much about this topic, i'm wondering if the granite slab is somehow adhered to the underlayment or does it just sit on top of it? if it is adhered to the underlayment, would that somehow prevent, "the effects of out gassing from the MDF"? if so, could you then seal the other support areas to prevent the out gassing? is there any way to get the contractor to do it the "correct" way?

When it comes to adhering using a construction grade adhesive, one that most people recognize is Liquid Nails but there are quite a few others out there with differing adhesive strengths and bonding to different material.

But in the case of an adhesive, typically one would incorporate a lazy S pattern of laying down the adhesive so there are many areas where potential gassing could escape any adhesive beading. Plus there's the underside of that particle wood that is the inside "ceiling" of the cabinet the countertop is attached to that is fully exposed to the storage area.

WindwardOahuRN
March 23rd, 2008, 09:25 PM
I wouldn't worry too much about the gassing as homes built here in Hawaii are pretty open (meaning not sealed like homes in the mainland). There's lots of cabinets and even those computer desks and entertainment cabinets you by and assemble have some level of MDF. Lots of today's speaker cabinets (your subwoofer in your living room) are made of MDF as well as those sub boxes in cars.



I was thinking the same thing, Craig. Unless you live in an air-conditioned totally sealed house (and I do know some people who live this way in Ewa Beach and Kapolei) I think the dangers of inhaling the formaldehyde gases would be minimal here.
Windows open, trades blowing...should be okay, I would think.

craigwatanabe
March 23rd, 2008, 09:31 PM
Nuts, if you develop a sagging frame, then you must've gone el-cheapo on your cabinets. I've never seen such a problem, since the framework is always entirely supported by the cabinets.

It doesn't matter if you went cheap or expensive. Heavy weight on any framework will take it's toll on a cabinet. When you put heavy weight on the top you develop a high center of gravity. That weight will put stresses on all joints of a frame. On most cabinets you don't see cross-bracing. It's assumed that the countertop will act as the sheer support for ANY cabinet despite it's price and quality of construction. If the granite slabs are providing that sheer support, they will separate at the grouting or butt points in time. If you have a solid granite top, the stresses imposed on the countertop will crack that counter in due time.

And it's the opposite way around, the framework supports the cabinets as the cabinet is the framework and facade.

salmoned
March 24th, 2008, 05:25 PM
Huh? The countertop only provides support for what's on top of it. The cabinets are self supporting, as well as supporting the countertop. The countertop lies dead on the spacer frame, which lies dead on the cabinets. That is to say, the only forces on the countertop and frame (or underlayment) are from gravity and both are supported by the cabinets alone. There are no sheer forces in this situation [unless you're imagining a countertop with a large, unsupported overhang (which is NOT recommended)].

cezanne
March 24th, 2008, 07:53 PM
The only shear forces I can think of in this situation would be if it were an island type of installation. Where there could be a twisting motion viewed from the top or even a lateral shear (since there are no side wall(s) that it's attached to as in a typical wall to wall countertop).

Beachboy
March 25th, 2008, 08:25 AM
I was thinking the same thing, Craig. Unless you live in an air-conditioned totally sealed house (and I do know some people who live this way in Ewa Beach and Kapolei) I think the dangers of inhaling the formaldehyde gases would be minimal here.
Windows open, trades blowing...should be okay, I would think.

I understand all that, yet in some places MDF is outlawed! For what? because it is deemed unhealthy for humans. Sure most of us don't plan to go to sleep every night with a piece of MDF for a pillow. But I do have small people in my house, and they are everywhere in this house! They tend not to wash hands very often, yet love to touch everything they see! So, yes this could be a problem.
If just one country outlaws MDF, it's enough for me to consider the ramifacations of using MDF. I wish I would have been given the choice here with regard to using toxic building materials on my house!

craigwatanabe
March 25th, 2008, 10:17 AM
Huh? The countertop only provides support for what's on top of it. The cabinets are self supporting, as well as supporting the countertop. The countertop lies dead on the spacer frame, which lies dead on the cabinets. That is to say, the only forces on the countertop and frame (or underlayment) are from gravity and both are supported by the cabinets alone. There are no sheer forces in this situation [unless you're imagining a countertop with a large, unsupported overhang (which is NOT recommended)].

I will tell you point blank: Granite countertops need to be laid down on a continuosly flat underlayment and 3/4" ply or solid wood is an absolute must. Sheer forces include cabinets mounted to the walls and floors that shift due to floor or wall movement. The word sheer in this case implies lateral forces which has nothing to do with gravity.

Granite has veins that are their inherent weakness and if laid on an uneven surface varying in as little as a 1/16th", even a 40lb load will crack that 1" thick granite slab. Heck even the weight of itself can cause cracking if not laid correctly.

Sheer strength support is for lateral movement. But because of granite's high tensile strength, any lateral movement up to the limits of it's flexpoint (which is virtually 0%) will cause it to shatter at it's weakest point which could be any one of a number of veins running in any given direction of that slab.

If you want to (and it seems you have already in several instances) go ahead and don't use an underlayment but for the reasons stated above, that will be a sad mistake. I've spoken to many installers and ALL of them indicate the imperative use of a 3/4" underlayment when laying down Granite slabs.

Also it has been recommended to use treated plywood when laying down separate slabs or tile due to grouting. Grouting is water-based and is also porous (just like marble). Because of that water will seep thru the grouting and ultimately pool on the underlayment. Non-treated wood will retain moisture and rot. Once wood is wet or rotten it attracts nesting ants and roaches.

Regarding the issues of gassing, your wooden home is constructed almost entirely of Hi-bor treated wood (not too many places allow the use of Walmanized green wood), from the sub-flooring (if on post and pier), to the exterior walls, headers and studs to the trusses and pearlings.

Building codes here in Hawaii demand the use of treated lumber in all new home construction not only because of it's insect and rot resistance but because treated lumber takes longer to burn than non-treated lumber.

If you have desks, entertainment centers and other furniture made of pressboard (as in most cases) MDF underlayment is a moot point. BUT any underlayment is better than none at all.

Roger check your PM

kani-lehua
March 26th, 2008, 06:43 PM
okay. so i took a look at some cabinetry at home depot, iwilei, yesterday. it didn't look like it was solid wood?

escondido100
March 26th, 2008, 07:01 PM
i have intalled all the brands of cabinets at Home Depot and Lowes...... the term solid wood is misleading.....usually the face frames and doors are "solid " wood. the boxes are made from a variety of materials...... the least expensive ones are mainly particle board....you have to pay extra for all plywood construction.....and even then they sneak in some masonite and PB.
the secret to getting good cabinets is in the installation... there are many shortcuts that may lead to poor quality.... an experienced carpenter will know what details are important......in the year that i have been an installer for HD i have seen many nightmares of homeowner installs as well as carpenter installed cabs..... a good framer does not a finish carpenter make....however a furniture maker will probably never finish the job.... there is some middle ground.....
I have torn out PB cabs that have been installed less than 5 years.....they usually just fall apart once a few key components have been removed (thats my trade secret)good kitchen cabs should last about 15 years...... and they will if they are installed properly.....and yes the top of the cab provide alot of shear strength to the box. you should always have some type of structural top. there are ways to get that strength without it but again why give all the trade secrets away......
one thing i will put out there is based on my experience.(30yrs).... the best ready made cab available at HD or Lowes is "kraftmaid" with the upgrade to all plywood and NO melamine. there are still some cheesy factors with kraftmaid but from an installers point of view they are he best.the best route is custom local built but you will pay and wait for that option.

craigwatanabe
March 27th, 2008, 11:12 AM
...the best ready made cab available at HD or Lowes is "kraftmaid" with the upgrade to all plywood and NO melamine. there are still some cheesy factors with kraftmaid but from an installers point of view they are he best.the best route is custom local built but you will pay and wait for that option.


To me custom is the only way to go if you want quality and longevity in your cabinets, that way you know what's going into the construction and how it's being built. I leave the pre-fabbed units for garage storage. Kitchen upgrades cost a lot but will reward you with a huge return on investment come assessment time, why go cheap on cabinets or installations.

In an open house, prospective buyers will instinctively look at the Kitchen then the Master bedroom as their first impressions of a place to buy. And when in the kitchen they look at the countertops and faucet hardware then appliances.

When I check the integrity of a granite counter top (especially an island) I'll fill a glass of water and set it on it's top. Then I'll go to the side and give the side of the countertop a good tap with the open palm of my hand. If I see any ripple in the glass of water, I know no underlayment was used and I tend to shy away from these homes.

If you can spot a poorly crafted countertop installation with this simple test, I guarantee you will find many more surprises in the general fit and finish of the home build.

Working at Home Depot's Hardware department, I work with hundreds of general and sub contractors. A lot of them are honest but occasionally I will find those fly-by-night contractors who come in from out of state, buy inappropriate tools, fasteners and construction material for their builds.

Because "Bright" or non-galvanized nails are about half the price as the standard "Galvanized" 16-penny framer nails, some will opt on the cheaper nails. Hawaii's codes demand the use of Galvanized 16-penny nails for rough-in work framing because of the use of treated lumber.

On T-111 exterior trim the standard is the 8-penny boxed galvanized nail. I cannot believe how many carpenters don't know that and use inferior fasteners on home construction here. Come inspection time, these builds will fail and won't pass the "Final" inspection by the county Building Department.

I've heard of homeowners who've paid contractors and have since left only to find out the construction was below code. The homeowner is then faced with the reality of having to pull out all nails (despite the interior walls and exterior facades laid in place) and having to rebuild the rough-in (hence make sure you have a box of Manapua just in case:D)

Oh the horror stories I hear on a daily basis! Beachboy I'm sure you can relate to some of these.

If you feel your contractor is using sub-grade construction techniques, there are "Code-Check" flip books we sell at Home Depot near the Pro Desk that can help builders identify what meets code and what won't.

YOU WILL BE SHOCKED AT WHAT IS CODE AND WHAT ISN'T. I had an owner-builder buy a 32-inch wide stand up fiberglass shower stall from us because it's the only stall that would fit thru his bathroom door opening (walls and trim up already). He was told by the county building inspector that his shower stall was too narrow and he needed a 36-inch wide stall instead. Had he told the associate this was for a new build instead of a smaller remodel we wouldn't have sold him the narrower stall, but as an associate we cannot quote building codes to our customers. It is then up to the customer to make sure of what they need to pass code. I will generally hint at codework but will not state it to our customers or else I'll get disciplined.

He ended up having put in a more expensive custom built stall because it had to be fabricated within the bathroom to facilitate building code.

Another customer had to rip out and reframe his casement windows because the window sills were 1/2" too high from the interior floor.

Then there was the guy who ran 14-gauge Romex wire throughout his home for ALL electrical circuits because 14-gauge was cheaper than 12-gauge. Upon inspection he had to rewire all 20-amp and higher circuits.

Outside and shower "canned" electrical lighting demand the use of sealed enclosures.

Codes codes codes, and many times people won't pass inspection because of their lack of understanding of what they are and why they're put in there.

You need a fireproof backsplash for stoves against walls, GFCI for all electrical outlets exposed to water (such as in kitchens, bathrooms and all exterior plugs around the home).

You need self closing doors on all entryways from enclosed garages to the interior of a home.

On all new builds wired in with battery back up smoke detectors are required.

And that's just for standard builds. If you're building for ADA (Americans with Disabilities Act) compliancy, there's a ton more codes to adhere to such as countertop height, lever style door hardware, grab bars, hand railings and ADA compliant wheelchair ramps.

There's so much code out there it's almost mind-boggling. What seems like a safe build could actually be out of compliance with county building codes.

i-hungry
April 14th, 2008, 12:37 AM
Good thread on home improvement. I knew some of the information discussed but learned lots of details.

Just would like to add to the recommendation for the plywood underlayment. Yeah I realize I'm beating an already dead horse. But also consider the sink moreso for the vanity sink. The underlayment has to be cut to fit the sink through so the support is less than maximum. Of course the weight of the sink add to the total weight of the countertop. With that said, I wouldn't consider plywood underlayment as overkill. Its just enough.

On the topic of MDF, I thought the formaldehyde problem was more related to the modification of the material. It would be way more hazardous for the person who has to cut or sand the MDF boards.

I think its weird that they put MDF as an underlayment. I don't think I would change it. Just try to make sure the water doesn't leak into it.