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Achieving this is an engineering challenge; it’s not a simple as you might think. I’ll spare you the calcs but will show you how I designed one recently.

Deck Post Connection

There are many ways to do this, of course. This particular design applied to an existing deck that had developed problems over the years and the Owner wanted it fixed right. He had a lot to lose should someone go overboard – it’s about 30 feet to the hillside below.

That was the deal Scott Sedam at TrueNorth Development recently agreed to with a medium-sized, western builder. I was the engineering component of Scott’s Lean Team.

My piece of the job pertained to the structural aspects. My mission:

1) To identify inefficient construction;

2) To estimate its cost;

3) Recommend more efficient, greener methods.

At the end of the day we had to find at least two-thousand, choppable, hard cost dollars or our team’s time and expenses would be donated.

What made this particularly challenging was that we had no previous knowledge of this builder’s homes. What if they were already 100% green and efficient? I like donating to a good cause as much as the next guy, but a private, for-profit corporation?…

Accompanied by the CFO and an owner, we randomly picked one of their 2,000 square foot ramblers in the framing stage. Within five minutes I knew we’d be getting paid. Holy cow, I’ve seen a lot of overbuilding in my day, but this house took the cake. Here are some particulars:

The Engineer.

All of this builder’s homes are engineered by the same company, let’s call them Fort Knox Engineering, Inc. (FKE) Before my field visit I spent a day going through a plan set and was impressed with the level of detail FKE provided – four pages of plans plus four more of standard details. Not much risk that the framers would have to guess or call for clarification (if they actually read all that stuff.) However, I was shocked at the amount of wood and metal FKE called for. Particularly considering that these homes are in moderate seismic and wind regions with no snow load.

The Code.

FKE designed per the 2009 IBC, which is exactly what I would have done. But, if I were the engineer of record, I would have used a different approach for lateral (wind and seismic) design. FKE used only a few interior and exterior shear panels and drug (via drag struts) the rest of the house to them. I prefer using all exterior walls for shear which spreads the load out, minimizing drag struts and holddowns. [Drag struts are straps, blocking, or other horizontally-oriented structural devices that pull and push lateral loads from one part of a building to another.]  If you’re sheathing the exterior with OSB anyway, why not have it do some work? Also, I avoid interior shear walls, mostly because getting lateral loads to them from roof and floor diaphragms can be difficult (read expensive.) Occasionally it does make sense to use an interior shear wall, but when I do, I carefully examine the buildability first.

I noted that FKE assumed a wind exposure “C”, which is for open terrain, and which results in relatively high wind loads. This builder’s homes, though, are always in subdivisions which are exposure “B”, a lesser wind load. So right out of the chute, the homes are overbuilt. I might add, they’re not in hurricane or tornado country either, in fact, the general locale has the lowest wind speed, 85 mph, allowed by code.

Straps and Clips Everywhere.

There were hundreds of these in this house. I think FKE must have stock in Simpson Strongtie Company. Now, mind you, I spec framing clips and the occasional strap too, but having been a framer myself, I know that every single one chews up a framer’s time and has material cost.

As an example, all the bird blocks had at least one clip, some two, connecting to top plates. But there were also hurricane ties on all the truss heels. If you run the calcs you’ll find that the hurricane ties alone keep the roof from sliding off the plate. You don’t need to clip the bird blocks too.

There were also straps and blocking around most of the windows. Here is another example of the engineer’s calculation method costing money. Shear walls can be analyzed several ways per code. FKE uses a method which allows less tall shear panels (a good thing) but with that comes the requirement of additional blocking and strapping around the opening. Sometimes this method makes sense but not here. This house has so much available shear wall that to fortify a bunch of window openings is just plain wasteful. I pity the framer cutting all those blocks and nailing all those lineal feet of strapping.

Wall Studs.

This house has 2×4 studs at 16” OC. Being a rambler (no upper floor loads) in a light wind area, studs could have been spaced at 24” OC. Also, many truss heels have double studs lined up under them which is completely unnecessary. This builder uses double top plates, a good practice I have written about, so lining up studs anywhere is pointless.

King Studs.

I was shocked at how many king studs were doubled. Not trimmers, king studs. The only reason for doubling a king stud is to take big wind load perpendicular to the wall (out-of-plane.) With light wind load and small windows, doubling make no sense.

Trimmers and Support Studs.

There were many instances where headers, beams, and girder trusses were supported by 4, 5, even 6 studs. If you actually calc what’s needed, you’ll find that a single stud works in most cases and a double takes care of the rest.

Cripples.

Doors and windows had cripples at the edges of the opening and at 16” OC. Here is a tremendous waste. Many times, zero cripples are needed. Sometimes only one will suffice. The rest of the time cripples at 24” OC works great.

Double Sills.

Every window had a double 2×4 sill. Why? A single would work perfectly well. I wondered if there would be some fancy wide trim or casing needing a lot of wood behind for attachment? No, not the case. It’s just how their framer does it.

Corners and Intersections.

All of these were old-school, 3-studders. There are greener methods.

Foundation Bump Outs.

There were bump outs for architectural features on the exterior walls. Each bump out is an expensive disruption of concrete forming. Generally, if the feature is non-load-bearing it doesn’t need a footing.

Double Interior Walls.

Certain interior walls were intended to have a wide architectural look, achieved using 2, 2×4 back-to-back walls. What about a single 2×6 wall? Almost as wide and a lot less expensive.

Anchor Bolts.

All anchor bolts were spaced 4-feet or less. That’s too many bolts, particularly for non-shear walls. One wall had them spaced at 3-inches on center. Yes, you read that correctly, 3-inches. I’ve never seen anything like it, just ridiculous. In a seismic event maybe 1/10 of those bolts would actually see any load, and if there were a failure, the OSB would rip apart from the mud sill way, way before those anchor bolts did anything at all.

Oversized Headers.

It was obvious that window and door headers were not calc’d. There were 4x8s where a 2×6 would work. Interior, non-load-bearing headers which could have been a single, flat 2×4 were 4×4 and 4×6. Just gobs of wood doing nothing, utterly wasted, using up space where insulation could go.

Those were just the big ticket items, there were many more ticky-tacks I won’t mention here.

I think you can see that my time was well spent, identifying well over $2,000 in savings. In fact, before I left I put together a quick spreadsheet tallying up $3,700+ worth of inefficiency – nearly double their goal. And my input was just a piece of our team’s overall mission.

Back in the office I created a Power Point presentation showing photos and explaining each issue. Here is the summary slide:

Correcting overbuilding WILL save considerable money without increasing the risk of structural failure, or violating code.

Steps:

1. Use a design team, engineer and architect, absolutely committed to green principles.
2. Revise house plans accordingly.
3. Make sure that concrete, lumber, floor joist packages, and truss packages are bid to 3 bidders each. Sole-sourcing guarantees inefficiency.
4. Train foremen and framers in green framing techniques.
5. Be prepared to save $3,000 – $5,000 per unit on concrete, wood, and steel alone.
6. Enjoy the benefits of a better-insulated home.
7. Optional: Inform plumbers and electricians that there will be a lot less wood in their way.  They’ll be the happiest subs on your jobs.

This was Scott’s 81^st Lean Team gig. I don’t know why I was worried going in – we’ve helped builders from New York to San Francisco and in every case unearthed thousands of dollars per home of pure, unadulterated waste. This client was no different.

So the story has a happy ending. We got soup, and the builder was ecstatic with their opportunity to save money without sacrificing integrity.

I say forced because prying the answer from our wonderful building code is like trying to wrest a fresh butcher’s bone from a junkyard dog. After much toil and sweat, however, I think I have succeeded.

First, let’s be clear what I’m talking about, this “blocking.”  Anyone who’s built a stick-framed wall in the past 25 years understands that blocking is 2x material positioned horizontally between studs, over which a horizontal joint in wall sheathing occurs. Many in our industry think that ALL such horizontal joints must have blocking behind.

Wall sheathing, for the sake of this article, is either plywood or Oriented Strand Board (OSB.) The building code allows other types but since most homes are built with these two, we’ll limit our discussion to them.

Way back in prehistoric times when I was a framer, before OSB was even invented, plywood was simply laid over wall framing and nailed off. Back then we used cave man devices called hammers to drive nails. A good framer could drive an 8-penny nail in one whack. I tried that once and drove the thumbnail right off my thumb so it usually took me two or three. Regardless, the number of nails required per sheet of plywood was pretty lax. Lazy framers didn’t use too many.

Then earthquakes happened and those lightly-nailed plywood walls didn’t hold up so well. Engineers and scientists studied the situation and determined that more nails were needed. Of course a nail through plywood into air doesn’t do much, so wood backing became required along every plywood edge, even the horizontal edges. Now we could get in lots of gainful nails and the assembly proved more resistant to lateral loading.

Building codes seized on this exciting development and gradually became more and more restrictive, to the point where, in 2003, the International Building Code required all plywood shear walls to be blocked. I’ve been engineering them that way since.

Enter green. If blocking and nails make walls stronger, why would anyone in their right mind not want to block? Well, if you’ve ever bought the 2x lumber, cut the block, bought the nails, nailed the block in place, and nailed the plywood to the block, multiplied by a hundred or so blocks per house, you know the answer.

Whether or not blocking is required today in 2011 depends on many things. The first is which code you’re using: the IRC (International Residential Code); or the IBC (International Building Code.)

I spent several hours trying to find the answer in the IRC, which is lightning-fast for finding anything in that colossal quagmire. Have you ever wondered why the IRC, which only applies to residential construction, is 870 pages, versus the IBC, which applies to residential plus ALL other types of construction, is a measly 678 pages? Dare I say that the IRC has become so bloated that its intended purpose of making residential design simple has achieved exactly the opposite? I digress.

You might think that the blocking answer would be right there in the tables defining what a WSP (Wood Structural Panel) is, in the Connection Criteria column? Or in the footnotes to those tables? Or in the other sections and tables that those tables reference? No, that would be too easy and obvious. Instead you have to go nearly to the end of the chapter, to section R602.10.8. There you will find this:

R602.10.8 Panel joints. All vertical joints of panel sheathing shall occur over and be fastened to common studs. Horizontal joints in braced wall panels shall occur over and be fastened to common blocking of a minimum 1-1/2 inch thickness.

So, seemingly, the IRC requires blocking everywhere. But wait, there are exceptions!

Exceptions:

1. Blocking at horizontal joints shall not be required in wall segments that are not counted as braced wall panels.

2. Where bracing length provided is at least twice the minimum length required by Tables R602.10.1.2(1) and R602.10.1.2(2) blocking at horizontal joints shall not be required in braced wall panels constructed using Methods WSP, SFB, BG, PBS or HPS.

3. When Method GB (Gypsum Board) panels are installed horizontally, blocking of horizontal joints is not required.

Upshot: Under the IRC, you must block all plywood- or OSB-sheathed walls that are counted as shear walls. Except, if you double the length required, those long sections don’t have to be blocked.

That’s pretty cool. I wonder how many building industry folks, code enforcement personnel included, know it? Regardless, it doesn’t do me much good because I loathe the IRC and don’t use it. Instead I use the IBC (International Building Code), though I have no great love for it either.

I could find nothing in the IBC, and I looked hard, that specifically requires blocking at ALL shear wall sheathing joints. What it does say, in section 2306.3, is WSP (Wood Structural Panels) “… shall be designed and constructed in accordance with AF&PA SDPWS.”

The AF&PA SDPWS is the American Forest & Paper Association Special Design Provisions for Wind and Seismic – the design bible for wood systems that resist wind and earthquake forces.

IBC section 2306.3 sneakily goes on to say that WSPs “… are permitted to resist horizontal forces using the allowable capacities set forth in Tables 2306.3.”

Why is that sneaky? Because of the words “are permitted.”  Those words do not mean “shall.”  So engineers can design shear walls per the AF&FP manual OR using IBC Tables 2306.3.

Most engineers don’t shell out the bucks to purchase the AF&PA and instead use Tables 2306.3. In doing so they are railroaded to footnote b of those tables which says in part, “Panel edges backed with 2-inch nominal or wider framing.”

There it is, the smoking gun seemingly requiring ALL IBC-designed shear wall edges to be blocked.

But a crafty engineer can determine how much wall is required to resist lateral loads, call that piece a blocked shear wall, and leave the rest of the wall unblocked, nailed like we used to back in cave man days.

Or, an even craftier engineer can shuck out the dough and purchase the AF&PA manual. In section 4.3.7.1.1 she / he will find this, “… All edges of all panels shall be supported by and fastened to framing members or blocking.”

Of course with a few exceptions:

Exception: Horizontal blocking shall be permitted to be omitted, provided that the shear wall is designed in accordance with all of the following:

a. The deflection of the unblocked wood structural panel shear wall shall be permitted to be calculated in accordance with Section 4.3.2.2

b. The strength of the unblocked wood structural panel shear wall is determined in accordance with Section 4.3.3.2, and

c. Specified nail spacings at supported edges is no closer than 6” o.c.

Upshot. These three exceptions allow unblocked WSP shear walls when the calculated lateral loads in them are low and there is a lot of solid shear wall (without doors and window openings.)

As an example, I just did the lateral design for a 2,000 square foot rambler in Anacortes, WA. Most of the exterior walls were long with few windows and doors. Thus the shear forces in them were quite low and I specified unblocked shear walls. However, the garage wall and one other wall on the view side had big openings (read, limited useable shear wall) causing high shear loads. Those walls I spec’d as blocked. On a percentage basis, approximately 85% of the house was unblocked. If I’m the guy buying and installing the blocks, I’m darned giddy about that.

I might add that if I’d analyzed this house using the IRC, interior shear walls and more holdowns than I used would have been required, costing at least the amount of my engineering fee (about $700.) And the garage wall wouldn’t have even been possible because it was “unconventional.”

In summary, yes, you can legally build unblocked plywood- or OSB-sheathed shear walls. If you’re using the IRC any shear panel that is double the length required can be unblocked. With the IBC, walls with low shear forces and lots of shear panel length can be unblocked, the forces and deflections determined by calculation.

It took a while, but my thumbnail eventually grew back. That blood-letting experience taught me something: The fewer nails you hammer, the greater your chances of walking off the jobsite with non-mashed fingers. This valuable lesson is one that all engineers should learn. Too bad it’s not taught in school.

“Yes,” I replied, “thank you for calling. How may I help you today?”

“Well, it’s my plant, you see. It disappeared. A lovely Dwarf Cypress, it was, in a 15 gallon pot. I went to water it the other day but when I got there it was gone: plant, pot, and all. Sunk into a hole in the ground right next to my house. My builder-friend thought I should call you about it. He’s worried that the house might fall in next.”

“How big is the hole?”

“Oh, it’s pretty small at the moment, maybe six feet around and five feet deep. I know my house won’t fit into it – yet. The problem is the hole’s getting bigger all the time. I think it has something to do with my basement pump because every time it  turns on there’s a new pile of sand at the discharge hose.”

“How big a pile?”

“Maybe a wheelbarrow-full a day. It’s making an awful mess of my lawn.”

“I’ll be right over.”

I got there and confirmed what Mrs. Schnitzelfritter had said. Large, fresh sand piles littered the west lawn. On the east side of her two-story house a dark, three-foot diameter hole in the ground yawned. Most disturbing was that the cavern extended under the foundation such that a 6-foot length was unsupported, hanging in air. It’s true, the house wouldn’t fit into the hole, but if the foundation was to crack, a large portion would sag causing severe damage.

Mrs. Schnitzelfritter showed me to the basement. It was 20-feet square, hand-dug, and neat as a pin. “Used to be I had to haul everything out in winters,” she said, “because water seeped up through cracks in the [concrete] floor. So about five years ago I had a basement pump installed. Everything worked fine until this winter. Maybe it’s because this was such a wet year, I don’t know, but in February I started noticing the sand on my lawn.”

The sump system consisted of an infiltration drain cut into the slab around the perimeter of the basement a couple inches inside the walls.  In one corner a sump pump was cut in that received drainage from the perimeter drain and from another drain, a four-inch pipe extending directly toward the sink hole, a few feet away on the other side of the wall. All workmanship appeared top quality – the contractor who installed this had integrity, definitely not a fly-by-nighter.

Inside the sump, silt had filled about two inches of the basin and was also visible in the four-inch pipe. I lifted one of the perimeter drain grates and found silt in it too. It was obvious that the drain system was transporting soil from under the slab and from outside the basement walls into the sump, which was then pumping it to the west lawn.

“Does the contractor who installed this know about the problem?” I asked.

“Yes, and he’s a very nice man. But I’m worried that he’s not going to take responsibility and I’ll be left with the bill to fix it. That’s why you’re here – to tell me whether it’s his fault.”

“In my opinion, there should have been a filter on the infiltration pipes; that’s pretty standard, especially in this agricultural area with fine-grained soils. Without a filter there’s nothing to bar sand and silt from being transported along with groundwater. The result is undermining. This system is defective and my report will say just that. In the meantime something needs to be done to stabilize your house. I recommend a couple of helical anchors to support the undermined foundation, and filling the hole with pea gravel.”

Using the word “defective” in a report is a bold move. It’s a fightin’ word – the kind that invites law suits. Not that I was looking to spark one, not at all. My purpose was to convey to the contractor that he caused a problem and now has the opportunity to step up and fix it.

I wrote the report and a week later the contractor called: “Hello, Mister Garrison?”

“Yes.”

“This is Gordon Lanyap, the contractor who installed Mrs. Schnitzelfritter’s drain system. I read your report.”

[Uncomfortable pause].

 “Yes. Did it make sense?”

“It made perfect sense, both to me and to the geotechnical engineer I hired to review it.”

Just what I expected – he hired his own expert. Now the fireworks start.

“Unfortunately,” he continued, “my engineer is one hundred percent in agreement with you. Which means I’m looking at an expensive fix. But I assure you, Mr. Garrison, I am a man of honor and integrity and will do whatever it takes to make this right. Can I hire you to design the helical anchors?”

Astonished, I was. What a pleasant relief. Many contractors would have dug in their heels, hired an ambulance-chasing attorney and put up a fight. But not Gordon Lanyap.

The next day I met Gordon and his geotechnical engineer at the site and we discussed the fix:

• Turn the sump pump off until all the following steps are done.
• Line the sink hole with a non-woven geotextile fabric.
• Fill the hole to the level of the bottom of the footing with washed pea gravel, using a concrete vibrator to work it into the gaps and voids of the soil.
• Install temporary blocking (cribbing) to support the foundation until the next step.
• Install two helical anchors through the pea gravel to permanently support the undermined footing.
• Remove and replace the infiltration system in the basement. This time use a multi-layer filter at all locations where soil can transport. I recommended a medium sand layer and filter fabric, but suggested that Gordon’s geotechnical engineer also provide input.

So this story has a mostly happy ending. The only negative was the cost and time Gordon incurred in the fix. Mrs. Schnitzelfritter’s basement is again useable, and luckily her home sustained no structural damage. I became friends with Gordon and have already worked on other projects with him. Gordon learned a lot about dewatering in fine-grained soils, about helical anchors, and most importantly about hiring an engineering expert up front. He also salvaged his good name and reputation – I, for one, will sing his praises and recommend him every chance I get. We all make mistakes – the difference between a referral and a condemnation lies in how we handle them. And finally the Dwarf Cypress was plucked from its holy grave and now sits happily atop terra firma where it always did.

Everyone, myself included, likes free advice. We all have nagging questions about things in which we are not experts. Things that if we guess wrong will cost us.

For example, a friend of mine is a chiropractor. I’ve got two teenaged sons playing high school sports and a wife who thinks speed-walking five miles a day is a wussy workout. And there’s me, the wannabe-video-game-hero who refuses to admit he just turned 50. We need chiropractic care pretty regularly. When I see my friend, Cracky, we usually talk baseball first. I coyly avoid mentioning the steak knives carving away at my spine until the moment is right, then I slip in a veiled request for free advice: “Sooo, Cracky, do you know anything about pain in the lower back radiating down the hamstring of a person’s left leg?”

His answer is always the same: “You bet I do. Any person with those symptoms needs an adjustment and should make an appointment right away. Not doing so can lead to a lifetime of misery.”

“Yeah, that makes sense. I’ll be sure to pass your excellent advice along to any such person.”

Cracky is great at answering the question without an answer. Me, however, I try to answer questions with an actual answer. Here’s a verbatim question from my website’s forum:

Hi Tim, I’m planning to install a code compliant egress window (28″ x 46″ overall) in my basement in a load bearing wall of 12″ cinderblocks. According to ilevl tables one 31/2 by 51/2 3′ beam would carry my loads (less than 1200plf). I plan to use 3 31/2″ x 51/2″ 6′long engineered wood beams glued and screwed together. The header will sit on two 31/2″ jack studs on both sides. There will two courses of cinderblock above the header. Is this an appropriate application of engineered wood beams or should I use a reinforced concrete lintel. I will be building a temporary support wall before cutting the window opening.

I’m pretty sure I understand the question. But am I sure enough to offer advice that, if wrong, could hurt or kill someone? Well, in this case I went ahead and offered a little but had to disclaim it because I don’t know: the type of engineered wood (there are several types with hugely varying strengths); the loads coming down on the header; how strong the “cinderblock” is (fully grouted, partially grouted, no grout, type of masonry, rebar size and spacing); how much wall will be left after the hole is cut in; how much dirt this basement wall retains.

The point is, there’s a lot to sizing a beam or header – more than most people realize. Unless an engineer has the full picture, i.e. an actual set of plans, he can’t definitively size any structural member, nor comment on the adequacy of the other affected parts (in this case, the rest of the wall and footings.)

But wait, you cry, what about published span tables? This fellow found one and deduced that his proposal was plenty stout. Still, he (wisely) had enough doubt to seek advice. What’s the deal with span tables – they’re so simple your Jack Russel terrier could use them, right?

Span tables are great if you understand every single number, row, column, title, and footnote (a biggie, that one) and use them correctly. The problem is, 95% of users don’t. I’m guessing at that 95% number – it’s probably higher. A common misuse, for example, is incorrectly accounting for loads; i.e. is the load on the beam you’re sizing truly uniformly distributed across the beam with no other concentrated loads?

Would you trust your spine to an accountant? Would you attempt that chiropractic adjustment yourself based on what you saw in a magazine or blog article? Maybe you could get your significant other or a co-worker to crack you? Why then would you attempt engineering based on a span table you’re not real sure about?

When I offer advice online I almost always include a closer something like this:

I recommend hiring a good engineer to help with these issues. S/he should take out any wasteful overdesign as well as ensure that there’s enough beef where it’s needed. An hour or two of his/her time will provide peace of mind and  is well worth the cost.

Is it possible for an engineer to only spend one or two hours on a project? Absolutely. I, for one, do it all the time. I find that most professionals are pleasers who care not only about the job at hand but the future job as well. If they can help, get paid for their time, and build a relationship, most are happy to oblige.

In conclusion, beware free advice, both giving and getting. On the receiving end, you pretty much get what you pay for.

Take the humble top plate of a stick framed wall for example. For thousands of centuries builders have used the Double Top Plate. As opposed to the Single Top Plate, which cuts the amount of top plate lumber precisely in half. Any progressive, green-thinking framer ought to wonder: why, then, even consider the Double?

I wasn’t around when the Double was invented but I bet I know how it became the standard.

1. Joining intersecting walls is easy and strong – overlap and nail off.
2. Same goes for in-line joining of the plate itself. Just overlap 48-inches and slap in 8, 16d.
3. You don’t have to worry about lining up rafter heels or joists with studs. The double plate can take those loads no matter where they fall.
4. Nobody cared much about saving trees.

Nowadays we’re deeply concerned with green, making the Single Top Plate a sexy option. But how to overcome the issues of joints, and rafter / joist loads that fall between studs? Fortunately, the building code folks have burnt the midnight oil and conquered these predicaments (Section 2308.9.2.1, 2009 IBC.)

In essence a Single can be used:

1. On bearing and exterior walls when joists / rafters fall within one inch of a stud, and
2. When joints, intersections, and partitions are connected with a 3-inch x 6-inch galvanized steel plate with six, 8ds on each side.
3. On interior, non bearing walls. An interesting note here: Section 2308.9.2.3 says, “… single top plate installed to provide overlapping at corners and at intersections with other walls and partitions.” So, how do you overlap single top plates? The code does allow in-line joints to be connected with a 2x, 16-inch long block or “…1/2-inch x 1-1/2-inch  metal tie with two 16d on each side of the joint.” That’s a tiny patch of metal with large 16d nails. I see those nails splitting the Single and poking through way too far. Why not use a bigger plate and more 8d’s?

But wait, as with most things in the building code, there’s more! Should your building be located in a moderate to high seismic risk area (Seismic Design Category D, E, or F – the entire west coast and other U.S. areas) and the calculated shear force in your wall(s) exceeds 350 pounds per lineal foot (a modest value), you must use 3x or double 2x boundary members. This would include top plates, bottom plates, and at all sheathing edges (Table 2306.3, footnote i, 2009 IBC.)

So with all the rigmarole involved in using Single Top Plates, I question whether it’s truly worthwhile? In rough numbers, given an 1,800 square foot home, a person could save about 400 lineal feet of interior and exterior top plate material using Singles. At $.40/foot this works out to $160. But offset that with the cost of all those metal tie plates and the hassle of lining up trusses and joists and are you truly ahead? Not to mention you can’t even use Singles in many parts of the U.S.

If I’m making the call, I’d stick with Doubles and rack up framing savings elsewhere, like right-sized beams, headers, posts, trimmers, king studs, cripples, wall studs, and foundations. Everything that glitters isn’t green.

The placard struck me as funny for several reasons:

1. This town and every other town up and down the west coast (earthquake country) is full of unreinforced masonry buildings (URMs).

2. This was the only such placard I saw in San Luis Obispo, or for that matter, in any town, ever.

3. The placard presupposes that a shopper will be prescient enough to know when the earthquake will hit and thus will avoid being in or around at that time.

So we’re left with a few questions:

A. Why bother with the placard?

B. How much risk is there, really, with unreinforced masonry buildings?

C. What can be done to mitigate the risk?

Before I jump into this article, I am compelled to tell you that I’m not picking on San Luis Obispo. I just happened to spend a couple sunny days there recently with my wife and college-bound son. We had a wonderful time – great hotel, great restaurants, shops, and the college was magnificent. I had my camera and did what I do while my wife did what she does: shops. This article could have been written about any town with old buildings. That said, here are my answers. I’ll start with “B.” 

Click this link for the full article: unreinforced masonry 1-30-11

Dear Don,

I was once told by a remodeler that if I would answer this very question and post it to my blog, it would be the hottest thing on the internet. Somehow I doubt that, but I’m glad to shed some light on an oft misunderstood and underestimated topic. Thank you for asking.

Following are the four main steps involved in demo’ing a wall or a part of one. Please understand that there are many ways of doing things – what I discuss below may or may not be exactly applicable to every situation. If in doubt, be safe: call in an expert.

STEP 1: DETERMINE IF THE WALL BEARS LOAD, I.E. IS “LOAD BEARING”

There are two types of loads that walls carry: lateral, sideways-acting loads from wind and earthquake; and gravity, from the downward weight of things above.

[Click the following link for the entire article in .pdf, with illustrations.] tearing out walls 12-29-10