Concrete Pads for Dummies

Pool equipment pad

When it comes to construction help, we're firmly in the camp who believe that someone who's actually done construction will be of more help than someone who's just read about it... or written about it. We already caught eHowian Larry Simmons exposing his utter ignorance of concrete work once before, so we weren't much surprised when another Simmons nomination came across our desk. This one's for the GardenGuides.com post (now moved to HomeSteady.com), "How to Build a Cement Pad for a Pool Pump."

We agree, of course, with Simmons that a pool pump shouldn't just be sitting on the ground, although his reasons for not using a wooden skid –

"a wooden base is subject to the expansion and contraction caused by temperature changes that would eventually loosen any bolts holding the pump in place"

– seem a little off to us. We think the expansion coefficient of wood isn't that different from that of concrete, but we do know that wood rots when it's just lying on the ground. Maybe Larry didn't know that? Of course, as with just about any other computer geek trying to write construction instructions, Larry quickly ran into trouble.

Simmons' instructions are (in theory) going to make a 2'x2' pad 4" thick. Larry wants to use 2-by-4 lumber to make the forms. Right away we noticed that he doesn't know the true dimensions of a 2-by-4:

• "...outline a square measuring 2 feet, 2 inches, on each side" – It's a quibble, but that would make a square 2'1" on a side, since a 2-by-4 is 1½" thick.
• "Dig a hole for the foundation of the pad 4 inches deep using a spade..." – First off, we wouldn't use a spade (they're for digging trenches). Second, that's gonna place the top of the pad half an inch below ground level, 'cause a 2-by-4 is 3½" wide.
• "Cut two of the boards 2-by-4 boards 2 feet in length and the other two 2 feet, 4 inches, long." – Yup, a 2' x 2'-1" rectangle...

Of course, Simmons couldn't find instructions for pouring a 2-foot square pad, so he cribbed them from an article on pouring a house slab. That's why he over-engineered his instructions like this:

"Fill the bottom of the form with 2 inches of gravel.... Place small concrete blocks about 2-inches square into the base of the hole to hold the wire mesh in place in the center of the slab..." Wait, what? He wants to put a couple of inches of gravel under the pad and use concrete reinforcing mesh? Really? For a 2 x 2 slab? Not to mention, where do you get "concrete blocks about 2-inches square ," anyway? Maybe if he'd read the instructions, Larry would have known that, He doesn't need that mesh for a slab that small. The slab should be sitting on a bed of gravel filled up to (about) ground level. Simmons' instructions would make a layer of cement 1½" thick. A 2-by-4 is actually 1½-by-3½. The pad should have some slope so water runs off instead of pooling.

Finally, Larry – having no idea what he's talking about – says nothing at all about the pump anchor bolts. Apparently he either thinks just resting the pump on the pad is sufficient, rather than setting studs in the wet cement and bolting down the works. Small wonder he's picking up his third Dumbass of the Day award!

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