As their name implies, precast concrete deck piers are ready made combination
deck footings and deck pillars all in one. The ones I used on one of my deck
projects were 54 inches tall. They were placed 48 inches into the ground so that
they were below the frost line for my local area. This left 6 inches of the
concrete deck piers above the finished grade for mounting the deck posts.
One of the main advantages of using precast concrete deck footings is that
unlike sonotubes, precast concrete deck piers won’t degrade due to exposure to
inclement weather, which is a common concern with building materials on a job
site. If a sonotube gets wet, prior to setting it in place and pouring the
concrete, the sonotube can potentially fail when the concrete is poured into it.
In addition, precast concrete deck piers are fabricated with a very wide base
for providing increased weight bearing support. They also have a threaded insert
cast on their tops for easily connecting deck posts to them.
Precast Concrete Deck Pier Disadvantages
The one big disadvantages of using precast concrete deck pillars is that you
need an excavator to dig the hole for them, and to lift and set them in place.
Consequently they may not be a great alternative for a DIY deck installation
project on an existing home.
The only other slight disadvantage with them is in accurately placing them so
that they are plumb and level, and situated exactly under the locations for the
deck posts. Once they are put into place, backfilled, and the excavator has left
the site, it is extremely difficult and costly to move them. Consequently, it is
important to know in advance exactly where they need to be placed.
Where to Buy Precast Concrete Piers
Precast concrete deck piers can often be purchased from precast concrete
suppliers who make concrete septic tanks and drainage pipes.
Precast Concrete Deck Pier Blocks
Precast concrete deck pier blocks are another alternative to using sonotubes. A
precast concrete deck pier block is designed to be placed into the top of a
concrete footing while the concrete footing is still wet.
Photo by Mark Donovan
To install a precast concrete deck pier block, simply pour concrete into the
footing until the concrete is within a couple of inches from the top of the
finished grade and then place the deck pier block on top of the poured footing.
Push the concrete deck pier block several inches into the concrete footing and
use a torpedo level to make sure the deck pier block is plumb and level on top.
It is also critical that the deck pier block be properly aligned. Use a plumb
bob to help with the proper alignment of the deck pier block. Gently tap the
pier block to put it in proper alignment. Repeat this process on all the
required deck pier blocks for the deck project and then allow them to set up for
24 hours before continuing on with the deck construction project.
For help on building a new Deck, see HomeAdditionPlus.com's
Deck Installation Bid Sheet.
Deck Installation Bid Sheet
will teach your how to hire the right deck contractor, and help to
ensure that your deck project is completed on time and budget.
How to Finance your Deck Project
can help provide funds for your new home improvement project if
financing is required.
Additional Deck Information