how to handle heavy objects in a pier and beam home

How to Handle Heavy Objects in a Pier and Beam Home: Sleeper Sills

Congratulations! Your grandma just gave you her grand piano. OR You’re going for that 80s vibe and bought a waterbed. OR You got yourself a big safe to store your piles of cash. OR You’re in Texas so you got yerself a big ol’ gun safe to store your piles of firearms ‘n’ ammo. 

support heavy objects in your pier and beam home with a sleeper sill
Awww yeah, check out this swanky waterbed . . .

In any scenario, you’ve got something heavy to keep in your pier and beam or crawl space home. Can your floors handle that heavy and/or oversized object of choice?

At Anchor Foundation Repair, we’ve been around since 1985 (consequently just in time for the heyday of the waterbed). We know a thing or two about how to prepare or repair your crawl space foundation due to an especially heavy item. We can tell you about a very simple solution that we often use in our house leveling repairs.

Your solution is called a sleeper sill. This article defines the sleeper sill as it is used in pier and beam and block and base foundation work. Then we explain how this extra sill beam is installed in your crawl space and how it helps solve and prevent foundation issues with all your favorite weighty stuff.

What Is a Sleeper Sill and How Is It Used In a Crawl Space?

Anchor Foundation Repair Bryan College Station

First a quick intro (or refresher) on the basic structure of a crawl space foundation. If you’ve already got a handle on these *foundational* facts about crawl space foundations, feel free to skip to the next section on the purpose of a sleeper sill.

In the beginning, your crawl space or pier and beam foundation is built layer by layer . . .

From the ground up, the layers go like this:

  1. Dirt/Soil/Ground
  2. Piers that elevate the home and transition up from the ground to the sill beams,
  3. Shims are inserted between the sill and piers to make small elevation adjustments and keep things as level as possible,
  4. Sill beams that hold up and support the floor joists,
  5. Floor joists that support the subfloor and the home structure,
  6. Subfloor that serves as an underlayment for your finished flooring surface, and
  7. Floor transitioning to framing and walls.
crawl space foundation structure

Sills fall in the middle of these layers and there are a few different types of sills that serve particular purposes or solve certain problems. A sleeper sill solves a very specific issue and is not needed in every crawl space.

In general, sills are large, long, and strong beams (typically made from wood on this home type) that help carry and distribute the weight of your home. What all types of foundation sills *do* is allow the structure to move from vertically oriented support with the stacked piers to a horizontal orientation by bridging the gaps between piers. 

You have main sill beams that are key structural components of the entire home. Main sills tend to run the full length of the home wherever they are placed, whether that’s on the perimeter or running through the middle under load-bearing walls.

Sleeper sills are typically added after a home has already been standing and only when needed. Sleeper sills don’t run the whole length of the home, they are comparatively short and placed only under isolated heavy objects.

Purpose of a Sleeper Sill

A sleeper sill is an extra sill beam added to the foundation structure. Sleeper sills give more support where a heavy object is placed. The sleeper sill beam’s purpose is focused on carrying the load of the massive and/or dense item so that the rest of the foundation is not overly stressed in one spot.

heavy object in home
This dude thinks you need a sleeper sill under that piano . . . and so do I.

When a heavy home fixture is put in a crawl space home without the support of a sleeper sill, floors begin to sag and dip towards the item over time. The wood begins to weaken, bend, and warp under the weight. Excess weight might even crack a floor joist or two or make a major indentation. We see this happen with cast iron tubs in addition to the other big stuff we’ve already mentioned.

Sleeper sills help to correct sagging floors caused by a heavy object that is already in place (as long as things aren’t too warped already) or prevent floor sag when a new heavy thing is being added to the household.

How Are Sleeper Sills Installed Under a Pier and Beam Home?

how sleeper sills correct floors sagging in a pier and beam home

Since sleeper sills are most often an add-on component of your home’s foundation, installing them is relatively easy. You do not have to replace something that already exists. There’s no *removal of the old stuff* to do. Better yet, you do not have to remove something that is sandwiched between a bunch of other interconnected layers of the foundation. It’s all-new and simple to add.

Here’s how a sleeper sill is installed:

  1. Identify the exact location where the heavy item is or will be,
  2. Place new base/block combo piers under the span where a sleeper sill is needed,
  3. Install a new, short 4 x 6” pressure-treated sleeper sill on top of the new piers,
  4. Use shims to snug and secure the space between the piers and the sill, and then
  5. Screw the sleeper sill to the bottom of the floor joists for long-term placement.

Sleeper sills can be installed as part of a house leveling repair project when you have other issues with your crawl space foundation. Or if your foundation is fine and you know that you’ve got a heavy object on the way, you can preemptively get just a sleeper sill added to your home.

Benefits of Sleeper Sills for Crawl Space Foundations

We kinda already mentioned these benefits, but we’ll repeat them for emphasis or in case you were *sleeping* and missed it. Sleeper sills are the solution for heavy objects needing extra support in crawl space homes for proper functioning. Adding a sleeper sill improves your home in these ways:

sleeper sills help support heave objects in your crawl space home
Something has got to support that safe of gold bars you have in your house, right?
  • If your floors are already sagging, sleeper sills help correct/minimize the sag or prevent additional sagging from occurring, or
  • Prevents sagging floors for anticipated or newly installed heavy items, and
  • Keeps undue stress off of your floor joists, subfloor, and flooring.

This is what foundation repair is all about for your crawl space home – everything working right and being well-supported so you can get back to enjoying life.

Check Your Crawl Space for Other Issues Too

Now you know all about sleeper sills and what they do. If you’re getting a sleeper sill installed, it’s a great time to look around your crawl space for other issues. Does your crawl space need to be cleaned out? Does your crawl space need other maintenance?

Install sleeper sills to prepare for heavy objects in your crawl space home

At Anchor Foundation Repair, we take our job seriously in caring for your home and setting homeowners up for the best possible outcomes. We want to help prevent future repair needs and issues for you whenever we can, whether that’s by installing a sleeper sill or suggesting cleaning or maintenance.

Crawl space homes always need some attention, they are not maintenance-free structures. Check out our recommendations with the Top 3 Maintenance Tips for Your Pier and Beam Home’s Foundation.