My video (bottom of this page) shows exactly how a pro adds a septic tank riser and a lid.
The above photo shows to topside of the cover. Below is a photo showing the underneath (bottom) of the cover.
These lids aren't sold at your local building supply stores. So where the heck can you find one?
The Sump Supply Store sells a 24" lid (including the seal and stainless steel screws). It's about $75 plus $5 shipping (pretty cheap shipping for such a large item!).
The description says it fits a 24" diameter pipe. Go measure yours before ordering!. If you need a 12" or 18" cover, click here to go to the manufacturer's web site.
It's made of high strength plastic and is lightweight. The lid can handle up to 2,500 pounds. The textured Lawn DecoTM decorative surface is non-slip. Underneath is a molded, replaceable water-tight seal designed to prevent ground water seepage. Square-drive stainless steel screws (no rust) are included for attaching to the riser.
See more information at the Amazon product page
Where to buy
a septic lid, riser, etc.
Click here to buy the 24" septic lid on Amazon.
The photo of the lid on Amazon looks exactly like the ones my septic professional installed (in the photo from the video, above). Compare the pictures for yourself.
I am just trying to help locate these supplies for whoever wants to do this themselves. I don't make or sell them. I just filmed my septic pro installing them.
You might be able to buy parts from a local septic guy or ask him where he buys his. I find septic guys to be very friendly and un-appreciated. We'd be up sh*t creek without them.
The dual wall riser pipe the septic fellow used in the video can be found at building supply stores, but you might have to hunt around to find one that carries 24". Lowes carries 24" dual wall polyethelene pipe but it comes in 20 foot sections. Probably more than you need. That's why calling your local septic guy might be cheaper to buy and easier to tote home. They might need $20 or $30 per foot of pipe or they might just give you some if you give them your future cleanout business.
The sealing foam used in the video is called Great Stuff Foam. Last time I looked it was under $4 at Amazon. And if you're buying over $35 of stuff (like a septic lid), shipping is free.
Stainless steel screws
#10 x 2 1/2" screws to connect the riser are available here.