Attaching to basement walls - Model Railroader Magazine

While I also recommend framing a full wall at your layout location I'll give my thoughts on direct concrete attachment.

I would recommend AGAINST a sealant  at your fasteners. If you drill your hole, smear some sealant in it and then insert the fastener the fastener now needs to rely on the sealant as a friction medium instead of the concrete itself. Also, if you have such a concern about water penetration now I would NOT put any holes in the wall.

I'll assume you have at least 6" of solid concrete wall there so you can safely use 3" to 4" of drill penetration IF USING a standard combo hammer drill (the kind with hammer on/off switch). If using more of a industrial drill then I recommend LESS drill depth because the hammer effect is 3 to 10 times stronger.  This added pounding WILL cause minute fractures in the concrete that may allow for water seapage depending on the grade of the exterior ground and water drainage at your house.

I personally suggest using 1/4" or 5/16" diameter X 3" (+) TAP-CON concrete screws. When I need to attach a 2x3 or 2x4 with heavy loads I'll take a 3/8" or 1/2" spade bit and create a 1/2" deep recess (think countersunk) and then drill thru the wood into the concrete. 

USE THE BIT SUPPLIED! Hole diameter will make or break the project! Drill to the needed depth and with the drill running slowly pull the bit out. This pulls most of the debris out of the hole and makes for an easier screw insertion. Get the screws with the hex heads and cooresponding size driver tip. Drive the screw on low speed, if the screws go in hard find an old candle and dig the screws tip iinto the wax about 1/4". The wax helps lube the screw a bit and does not hinder the holding power.

If using expansion type anchors I recommend NOT using the style that requires lag bolts. Get the ones that are a stud type anchor. Much more holding power and the almost never loosen up over time.

Ken aka "CL" "TIS QUITE EASY TO SCREW CONCRETE UP BUT TIS DARN NEAR IMPOSSIBLE TO UNSCREW IT"