How is the best way to replace pressure treated exterior deck flooring

Gail from G.D.
by Gail from G.D.

I live in Massachusetts so snow in winter warm weather in summer. I need to replace my pressure treated exterior deck flooring. Should I replace with pressure treated lumber or go with a TREX type of flooring. I was told todays pressure treated lumber is not chemically treated like it was years ago so the lumber will need to be replaced sooner but TREX will last longer. Suggestions please!


  10 answers
  • Cynthia H Cynthia H on Jun 02, 2020

    It depends on your budget and how long you expect it to last. If you can afford a product like Trex, and you want it to last (check the warranty) it might be your best bet. Good luck and stay safe!

  • Ken Erickson Ken Erickson on Jun 02, 2020

    TREX will last a long time and looks nicer than PT decking. Check with dealer about floor joist requirements. I was going to use it on an existing deck with 24" on-center joists and was told that the maximum joist spacing was 16" on-center. I went with redwood instead so I didn't need to install more joists.


  • Gk Gk on Jun 02, 2020

    I replaced my deck flooring which had been pressure treated lumber with new pressure treated lumber. The old deck flooring lasted 30 years because we treated it every few years with deck products. I do believe that if you treat your deck flooring about every 2-3 years with a GOOD deck product you can keep your pressure treated lumber looking good for many years. I have learned to use an oil based deck product that soaks into the wood rather than a paint type deck product that just sits on the top like paint--that paint type deck product will eventually peel and bubble and it is a NIGHTMARE to get it all off--sanding, sanding, sanding--to apply new. Today I stained my new deck boards with an awesome product--Armstrong Clark stain. It is an oil based product that soaks into the wood and will NEVER peel and bubble. It is the second time I have used this product in five years--LOVE IT! No more peeling or bubbling--it just fades with time and looses it's water resistant properties. All you have to do is clean your deck well before applying a new coat. I did wait a year before I applied the stain to my new deck flooring so that it was dry and would accept the oil and stain color. I live in northern Minnesota with LOTS of snow and ice and this is the best thing I have EVER used! The Armstrong Clark products are the BEST and I will NEVER use anything else! (Sorry for sounding like a commercial!)

    https://www.armclark.com

    I did consider the Trex type of deck boards but it was less expensive to use pressure treated lumber and faster to do. I have also heard that the Trex type products get very hot on bare feet. I have also heard that they are difficult to stain if they fade.

  • Annie Annie on Jun 02, 2020

    Before you begin your project, be aware when you remove old deck material, the joists may also need replacing. I would go with ALL presure treated lumber and put a good coat of stain, even on lumber below the deck. It may be a good idea to have a carpenter take a look just to be safe.

  • Redcatcec Redcatcec on Jun 02, 2020

    Here's a comparison, pros vs cons:


    https://www.deckmaster-us.com/wood-vs-composite-pros-cons/


    Also a handyman just told us this week that Trex is slipperier, especially in winter.

  • Kelli L. Milligan Kelli L. Milligan on Jun 02, 2020

    The first thing to consider is if you have to rebuild the joists to hold the trex. The have to be much closer than the standard 16" as with treated lumber. Until you are ready to replace all the boards at once is just replace the rotten ones with the same. Research in your area what is available. There are other products other than Trex and treated lumber.

  • Vimarhonor Vimarhonor on Jun 02, 2020

    Hello. It depends on your budget.

    We have both a pressure treated deck and a Trex Havana Gold front porch elevated entry.

    There’s lots of benefits to the TREX including the decrease maintenance.


    We are constantly pulling up pressure treated boards and replacing them they do degrade with exposure on our rear deck and boat dock. In our particular situation with heavy sun exposure we are constantly resealing our deck it seems like it needs restaining every year.


    But pressure treated is much less expensive than TREX. Budget wise sometimes replacing 10 or 20 boards a year is much more cost-effective than several thousands to do the replacement with composite.

    Also which might be a factor sometimes additional supports are needed for the composite material. In our case it came to our budget for our boat dock $8000 to put the composite on the existing structure PLUS add additional support vs replace a few boards as needed.


    We are very happy with our composite- but it comes at a significant cost.

  • William William on Jun 03, 2020

    Cost is a factor between pressure treated and composite decking. If you stain or seal pressure treated it should last. The only difference with the old pressure treated wood and new is that newer is not treated with arsenic like the old.

  • Kathy Gunter Law Kathy Gunter Law on Jun 03, 2020

    If you can, trex would be best. The chemicals are different now that in years past and aren't as strong but you can combat that by using a weatherproofing sealant annually if you go with regular PT wood.

  • Rae Rae on Jun 03, 2020

    I am on the the 25th year of our pressure treated deck. We have fairly harsh winters and it is on the south side of the house so gets full sun. Yes there are a few boards that are a bit rough but all is still sturdy. It has never been painted but about every two years I clean very well and reseal it. It isn't maintenance free but if cared for properly it will last a long time. I've thought about replacing it with a product like Trex or another name but i would have to take out a loan since it is so large!