What size of beam should I use to replace 3 2x8 that is 16 feet?


Part 3 of Residential Structural Design

On this page we will explain how to read and design with floor beam span tables. You'll find a beam span calculator towards the bottom of this page. This site also has information on learning how to read joist tables and a joist calculator.

If you are just starting out, you might want to go to the joist page since we will expand on the house design example introduced there. Or even go back as far as the residential structural design page which explains basic house structure.

Or see our Design Your Own House tutorial site map.

Using Floor Beam Span Tables

Continuing on from Part 2: Wood Joist Span Tables of Residential Structural Design, we were just about to make our example house wider. Once we go beyond the allowable spans for floor joists (as shown in the floor joist span tables), we will need some kind of support under these floor joists.

This support could take the form of a structural wall....

0 0
Over my head

Sorry, I took a look at both of those links and I feel I am in over my head. I don't understand Modulus of Elasticity, etc.

Plus they are talking about joist spacing, but I'm having a hard time understanding how to correlate that to a single beam span across to end anchor points.

in the usplasticlumber table, I assume this is for plastic wood, so I'm not even sure the numbers should be used for tree wood...

for an example at 120F, they list a span for 100 psf Live Load. Does this mean 100 pounds per square foot, and if I want to have the 2x4 beam support 300 pounds in it's middle (again assuming that's the weakest point) I can only have a span of 25 inches? That's too short of a distance, and the 2x5 beam does not appear to be much better. I need to span a 10ft horizontal.

The other page with calculations confused me. Can you sugest other websites or search terms that I could use to try and find a method to calcualte this?...

0 0

Been there, done that, (missing verb) it up.

In my first effort I used 2 x 10 cedar beams glued and bolted together. Looked great - about 20 years later we got home after a night of heavy wet snow to see that the thing had partially collapsed. Turned out the wood had rotted around the bolts ..

When we bought this house in Lethbridge - it had (and still has) a classic open pergola roof sunroom at the back. It has 2 x 10 beams and they're fine but.. the people who built it didn't think about foundations enough. Two years ago I had to shore up the walls, remove the deck, dig out the muck
underneath, and replace the foundations with 6" concrete posts dug and hammered 3 ft down, then put new floor beams and deck. (and now she wants it replaced with a glassed in sun-room )

The point is that not thinking about what water and bacteria will do to your design will eventually bite you, or somebody else, where it...

0 0

Total load in pounds = FBd^2 / 9L.

Fill in the parts of the formula that are already known. L stands for the span of the beam, in feet. In the example, the beam spans the 10-foot width of the roof. The total load is 4,000 pounds. F stands for the beam's fiber strength in bending, which depends on the species of wood. For the initial calculation, F can be estimated at 1,000. Now the example formula is 4,000 = (1,000)Bd^2 / (9 x 10).

Choose a convenient value for B, which stands for the breadth of the beam in inches. A typical beam breadth is 6-inches.

Rearrange the formula to solve for d, which stands for the depth of the beam: d = square root of ( (load x 9 x L) / (F x B) ). In the example, d = square root of ( (4,000 x 9 x 10) / (1,000 x 6) ).

Calculate the initial value for d, then round it up to the nearest inch. This tells you the size of the beam needed to support the porch's roof. In the example, d calculates to 7.75. This means the example...

0 0
Doable, yes.

Practical, hmmm?

You mention that your barn is 36 feet wide with beams set on 12 foot centers. How did you come up with a 16ft span?

For 4 feet more span, I'd say your crazy to waste your time and money.

If you mean to span the total distance between the posts and go for 24 feet, you better get an engineer for that one. 16 feet isn't that big a deal for some 2x12 with plywood. Garage doors do it all the time.

If you really want to increas your 12 ft span to 16 foot, then your talking about relocating one or both posts.

What are they supporting?

Is there anything tied into the beam?

Taking out one piece of wood to replace it with another affects every part of the framing around it. Lots of times it's not a significant change, but without pictures and/or an onsight evaluation, you'll never know for...

0 0


Brice Cochran has been working in the timber frame industry for over 14 years as a timber framer in the shop, project manager, and designer. He finished his own 3,000-square-foot timber frame home near Mountain Rest, SC while working in and on his timber frame design business Whetstone Designs and Timber Frame HQ. At the University of North Carolina, he studied Philosophy and Mathematics. He is an active member of the Timber Framers Guild and the Timber Frame Engineering Council. He is married and is the proud father of two children.

Q: How does timber framing fit in a green building environment?

A: (Will Beemer) Use local materials. That to me, is one of the major components of a sensible building system. In New England, where I live, our forests are mature again and we have plenty of good timber that can be sustainably and selectively harvested and processed at local sawmillls. Portable sawmills are also very popular that can go right into the woods....

0 0

NOTE: Version 4.0 May 12, 2011 -- Added step 7 about a brief trimaran conversion for the Everglades Challenge. I talk more about sailing (and other things) at my blog, Tristram Shandy in the 21st Century, www.tristramshandy21st.blogspot.com --wt

Foreword According to the philosophy of "one boat for each day of the week," I built my Tuesday boat. The Monday boat was described in my instructable, Make Life Better with a Sailboat in a Closet. This Tuesday boat reflects some lessons learned from the Monday boat, some changed situations (for context always has a finger in the things we build), as well as the usual misguided notions that exist to help us set benchmarks for all human values.

What it is This boat is a tacking outrigger sailing canoe. It is a 3-board canoe, which means, in Western boat-building tradition, the main hull (vaka, in Pacific boat-building tradition) is a sharpie-style hull. However, the outrigger float (ama), is a two-board hull (Wharram...

0 0

I got about 80 pallets, five at a time, from my work.

I got a chance to know the facilities people and they were very happy to let me take them. It saved them a trip to the dumpster and saved them from having to pay to have the dumpster emptied.

That's right. Almost all of these pallets go directly to a landfill. The rest are picked up by pallet salvage guys (they get $1 or so a pallet) and people like me. Many people burn pallets for heat.

I got a great deal of exercise carting the pallets out to my Jeep. I could fit about eight at a time, but I rarely found more than five good ones on any given trip.

A few words about pallets:

There are all sorts of them. Some are oak, some are pine or spruce. Some of them are even mahogany or cherry or cedar.

Stay away from the hardwood pallets. They"re almost impossible to deal with in large numbers. They are just too darn tough. Unless you're doing something small or you want them for fire...

0 0
0 0
Trimble Trimpack Transpack Transpac Transpak GPS receivers©

Brooke Clarke, N6GCE 2003 - 2016

GPS Receivers
Part Numbers
Trimpack SLGR AN/PSN-10 "Slugger" L1 3 Channel
Tanspak L1 3 Channel
Function Switch & Menus
Dead Power Supplies
TransPak II L1 6 Channel
Trimpack II
P-Code & SAGR
Centurion p/n 18154-00 Model:20636-00[SM]
Common Features
Military Antenna 17572-00
28367-40 Mag Mount Antenna
4000ST/SST Antenna
21423-00 white hockey puck
Commercial L Band Amplifier
Back Up Battery
Computer I/O Mystery Cable
GPS Week Rollover Bug
Power Sources
Hardware Options
GPS Frequencies
Related GPS Receivers
0 0