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By Chris | October 21, 2008 - 7:51 am - Posted in Big Timbers, Plans, Structural Components, Treated Wood

Wood bridges offer ways of crossing natural settings with structures that fit the surroundings.? Although wood bridges are not practical for every application they are perfect for many – affordable, simple, durable, and beautiful.

Affordable:? Depending on the design, wood bridges can be built for as little as 1/3 the cost of steel and concrete bridges and have lower maintenance costs as well. Building wood bridges over crossings might be a great way for landowners and small municipalities to save money as well as add aesthetic value to their byways.

Simple:? Many practical wood bridge designs require less skilled labor (no welders or concrete workers and smaller equipment) to assemble and less time than steel and concrete bridges.? Simplicity equates to a savings of time and money.

Durable:? Effectively designed and constructed wood bridges should easily last 50 years and there are many that have been in services for much longer than that. Wood treatments and coatings available today should protect the foundational structure of a bridge so it will last virtually forever.

Materials for Wood Bridges

Like any project, wood bridges will last longer when built with three major components in mind.

  • Quality Design
  • Quality Materials
  • Quality Construction

We will focus on quality materials for wood bridges here.? You can buy bridge plans or have yours custom engineered and you can hire a bridge building company, local contractor, or build the bridge yourself with the proper design and instructions.

Use properly treated wood for your bridge components, especially for the pilings and other foundation materials.? .60 pcf treated wood should be sufficient for most locations but if you are building around saltwater, you should probably use a stronger treatment for the foundation components – especially if the bridge will actually be in contact with saltwater.

To add longevity to your bridge use poly coated wood like the stuff from American Pole And Timber (they also have a full line of bridge timbers and bridge decking) for all of the ground contact components.? It is sprayed onto treated wood before installation and provides an extra layer of protection that should easily add another 25 years to the wood (at least). It actually bonds to the wood but you can still cut, nail, or drill into it.? It is really good stuff – initially designed for use on saltwater marine pilings (where is has a 25 year warranty).

Your wood bridge’s hardware should all be stainless steel, galvanized, or zinc coated.? There are other special hardware coatings out there but stainless, galvanized, and zinc are proven and affordable.

Plans for Wood Bridges

Buy Wood Bridge Plans Online:? There are numerous places to buy wood bridge plans online – so many, that I will not even link to them here.

Bridge Plans from Competition:? Here are some great bridge designs and plans I found recently. It is a wood bridge building competition for University-level engineering students. “The? National Timber Bridge Design Competition? is open to student chapters of American Society of Civil Engineers (ASCE) and Forest Products Society (FPS) in the United States and Canada. Joint or cooperative entries (ASCE and FPS working together) are eligible and even encouraged. A chapter may also submit multiple entries.”

The young folks in this competition come up with some creative, effective, and practical designs for wood bridges.? You might be able to apply a few of them to your wood bridges. Note:? That is not a suggestion to copy the designs or use them directly as reliable and tested plans but there are some great ideas there.

Book about How to Build Wood Bridges:? This is a really nice book that has some designs and plans for building wood bridges as well as plans for building other wood projects.

Wood bridges can certainly be built as a diy project. Please make sure you have your bridge professionally designed, though, or at least hire a professional contractor to help you. Using the right materials will not only improve the safety of your structure but will ensure that your bridge will be long-lasting as well. Wood bridges should be built to last – they should stand as legacies to be used for generations to come. That might sound nostalgic or something but, well, I guess it is.

By Chris | April 23, 2008 - 3:33 pm - Posted in Poles, Posts, Pilings, Specs & Data, Structural Components

I am regularly asked about pole prices - everything from prices per size to freight costs and installation, etc. The object of this video and chart is to briefly explain the basic pole prices relative to length, the most commonly discussed characteristic of the pole.

Poles come in numerous sizes, species, grades, and treatment levels. Each of those factors affects price. The biggest factor affecting the delivered price of a pole (treated or untreated) is sizemostly length – and that can be broken into two main reasons.

  1. Supply: Trees take a long time to grow and BIG trees are getting scarce.
  2. Freight: Permits and special equipment are probably required for long lengths.

In fact, if you order an 80′ long pole today it is likely the tree you will receive is still in the forest today. Crazy, huh?

You need to a flashplayer enabled browser to view this YouTube video

The chart does not appear clearly in the video. Here it is (below) so you can get a better look.

Don’t use this chart to bid your next project or anything. I simply wanted to make the point that around the 50′ length mark, the pole prices curve turns sharply north. Also notice that the incremental pole prices on the left get larger as well. Yes, it is certainly possible that you might pay $5,000 (delivered) for a 90′ pole. Don’t even ask about poles beyond 100′.

Pole Prices Chart -Prices versus Length

You should always design based on the needs of the structure (as opposed to what materials are cheapest) but “value engineering” is always important to keep budgets in check and projects affordable. With that, if you are building a structure that requires poles longer than about 50 feet, you might consider brainstorming ideas to design the structure so it can use shorter, less expensive, poles.

Basic Take Away about Pole Prices (in a rhyme): Under 20 feet, poles are cheap, beyond fifty, prices are ‘iffy. :)

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