Decks/New Deck Beams


Deck Beam
Deck Beam  
Porch Beam
Porch Beam  
QUESTION: I have new porches and a 10x12 deck that was put in last month. I now notice some of the beams don't look right and they are splitting all over the place. My question is what do I do? The contractor said he could put car bondo on them but that sounds ridiculous or is it?

ANSWER: Hi Annette,

    Yes, Bondo sounds pretty ridiculous to me too. I have never heard of using Bondo on wood like that. Those girders look to be possibly 4x6 or 4x8. It's hard to tell from the photos. Although it's not a crazy idea to use the 4x lumber, he would have been much better off using 2 or 3  2x8 or 2x10s fastened together to create a girder. Thicker pieces of tree (such as 4x4, 4x6, 6x6, etc) tend to check and split more as they dry. They also tend to warp and twist more, which I can see is also happening there. If it were me, I would temporarily support the deck, take those out, and use the multiple 2x sized boards instead. They also must be crowned up, and fastened together properly, with bark sides out to minimize sagging, twisting, and cupping. There should also be a "hurricane tie" type bracket installed from the girder to each and every joist that sits on it.

Hope this helps, and let me know if you have any further questions.  :-)


---------- FOLLOW-UP ----------

QUESTION: I talked with my contractor and he refuses to replace them. And yes you are right they are twisting and warping. So my next question is what will these beams do next and how soon will I have to replace them? They look like they have been on there for years and it has only been a month.

    They do look abnormally aged. Are you sure that they are pressure treated? If they are not, then they absolutely must be replaced! What state are you in. I'm in NJ, and we have nice looking pressure treated Southern Yellow Pine here. When I was out in Southern California a few years ago, I visited a local Home Depot, and all of the pressure treated lumber had those dashes cut into it, like I see on your joists there. That 4x6 beam under doesn't have that? The red end is also kind of suspicious, as red and blue ends are commonly not pressure treated least not here in the Northeast. Did those 4x6s look bright and new when first installed? It looks quite gray already, especially for not being in direct sunlight often.

    Another factor to consider (which I cannot see in the photos) is how far apart are the footings that are supporting the 4x6s? I probably wouldn't span those more than say, 6' max. If the footings are further apart than that, I would expect those beams to sage in between each of the footing, and they will sag even more if they are not pressure treated type lumber.  


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Michael Romano


I can answer any questions relating to decks, porches, exterior stairs & railings, walkways, access ramps, pergolas, deck roofs, screen rooms, etc... These may include design ideas, footing to framing design & construction methods, various species of woods vs. composites & pvc/vinyl materials for decking, skirting, or railing applications. I also have expertise in various rain-free systems for under-deck storage & living spaces.


I have designed and built decks and many other types of outdoor structures for over 25 years for my own home improvement company. We also perform many other types of home improvements, including window & door installation, molding & trimwork, siding, basement finishing, siding, etc. Our main love however, is decks!

NADRA - The North American Deck and Railing Association. Several Small Business & Home Improvement Contractor Alliances & Associations.

I have written several articles over the years for,, and many other deck & construction related websites.

High School graduate. 2 years of Mechanical Drawing & Architecture classes. Vocational School graduate. 2 years of Construction Technology & Carpentry classes. Many years of reading, researching, and application in the real world.

Awards and Honors
I am certified by several decking manufacturers for expert application & installation of their products.

Past/Present Clients
Mainly local residential clients, and occasional commercial clients, including restaurants, nightclubs, office buildings, etc.

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