How to Extend a Deck and Fix Rotted Support Posts

by Bhupendra Mistry
(Nepean, Ontario)

I have a 10x12 deck that is 10 feet high and 20 yrs old. Its attached to the house and supported by square posts made of 2x10. The support posts and beam are 8 feet out from the house.

The support posts need to be replaced. There were set in concrete and may be softening inside.

I want to extend the deck by 2 feet in length and width to make it a 12x12 deck.

What is the minimal that I need to do?

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Sep 18, 2018
by: Mike

Can I get more details and where to order?

Oct 08, 2013
by: Editor

Actually, it was just approved with a new patent from the USTPO which is always nice.

But I still have to tool up to make the first run of them. It is a very niche type product so not something that everybody will need.

But if you need it, you need it. So it will now be a reality.

Mar 20, 2013
New Product
by: Rich R PA

I was justreading your article for repairing post problems that wasn't ready for the masses.Has this become available yet.Thanks for your help.

Sep 06, 2010
The Atlas support post base is coming soon...
by: Editor - Rich Bergman

I have received a number of emails from people over the past 6 months asking me about this new product I am developing. All these folks have support posts that are rotting at the base of the post where it contacts or is very near to the concrete pier or footing.

Of course most of these problems could have been avoided if a raised stand off post base had been used. Something like the Simpson products available most everywhere.

However, these products, while perfectly performing from a functional perspective are purely utilitarian. They don't look fancy, because in many cases folks don't need them to be. If you live in an area with 4 seasons and there is snow or ice build up from time to time - or I suppose even just a ton of rain or moisture, then this kind of support anchor won't give you all the protection you need from the elements.

You will be looking at post base rot in due course.

Also, many of the people contacting me were not using pressure treated posts but beautiful red cedar or redwood posts. I was a bit surprised to hear one single 4x4 redwood post, 100" long was $120 to replace. Imagine if you have 16 posts rotting. Imagine if they are 6x6 posts 14' high! Yikes.

So you will really appreciate the Atlas as it allows you to save these posts with and keep them dry using a really cool patent pending water tight seal. It is designed for new construction but will be a true life saver for repairing rotted posts.

And of course with all the Titan brand products you can expect the design to incorporate not just performance but good looks. It will look nice on your home.

Coming in spring 2011. I'm working like a dog to get it perfect... Thanks for your patience.

Apr 27, 2009
Rotting Deck Support Posts and Deck Renovation
by: Editor - Rich Bergman

Rotting deck support posts is a perennial problem and the solutions out there are limited. To enlarge the deck as you wish you must do a couple things.

Increasing the Width Along House

To make it wider you will need to extend the length of the beam. The easiest solution is probably to build a new beam and replace the old one while the entire structure is temporarily supported.

This would also require relocating the support posts. You might have to go from two posts to three. If so you would probably need posts 12" from each end and one in the middle.

Increasing the Length

There are limits to how long certain joists can span based on their size and how close you center them. Also there are limits to how far you can cantilever the joists beyond a beam. Go see your local building department for their up to date tables. They deal with this all the time for building permits.

But I think you will have to move the beam from 8 feet to about 10 feet from the house. This may be beyond the load capacity of the existing floor structure. Again, go see your building department.

Rotting Support Posts

This is a problem. It would be nice to save the posts. But rot tends to go up like a cone inside the post. If only the lower 1-2" is rotted it is likely rotting 4-5 inches up inside. Since post anchors only extend usually 1-2" you are out of luck and have to replace the entire post.

But not for long. I have a new product that is designed to solve this exact problem and looks really nice. It saves you the labor and materials expense of replacing the posts.

Its not yet ready for the masses but will be soon. You can call me to discuss this anytime at 866-577-8868 or use the Contact Us form to email.

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