My friend Laurie leased this house several months back. The front retaining wall had been in the condition shown below for quite some time, and since it is the first thing any visitors see upon entering, I can't fault her for wanting it fixed. The part that bothers me is that a motor vehicle apparently hit the wall after the driver ran a stop sign and/or failed to negotiate a turn, and if I know my town, the police were there writing up the report within two minutes. You KNOW the landlord must have collected at least a grand. Oh, well....I guess we've all been there and done that. She asked me to take a look.

Frankly, this wall should have been taken down and completely rebuilt. I'd have done it for $1100. To repair the existing wall, I put in an estimate of $500 for which I would have removed ALL damaged brick, stone and block and rebuilt it with new material, probably throwing in some cutesy brick bonds since 80% of the face had damage and I like doing unusual stuff. (I was thinking maybe a 3 brick stack that turned 45 degrees every two feet until it did a full somersault. I'll do it somewhere else some time.) The landlord rejected that one as well. I guess he had in mind that he'd fix it himself some sunny day. So I told Laurie that I'd do it for nothing except my own amusement - sort of a housewarming gift. IF I actually relied on this work to keep a roof over my head, I imagine I'd be doing a great deal of these little patch and point jobs, so I was curious if I could tolerate it. It was perfect! I would never have selected this particular brick (scored face, but otherwise traditional red clay). It neither thrilled nor offended me, and a close match was readily available at Boychuk Stone Co. I can't imagine that I would ever build a wall in straight stretcher bond either, so the challenge was really to keep my imagination stifled and the cash outlay for material to a minimum.

Whatta we got here? After clearing all the loose debris, I was better able to assess the damage. It's pretty extensive! We basically have a concrete block wall with a brick veneer. There are (were) strap ties (corrugated, galvanized metal tabs) fastening the brickwork to the mortar joints in the concrete block all along the midline. I'll assume the foundation is adequate since there is not a single crack in the brickwork of the bottom two courses. The force of impact shattered many of the bricks I pulled from the "hole" area, leaving them unsalvageable. There are severe structural cracks in the exposed concrete block, and not a whole lot I can do about it without some further demolition.

First, I cleaned as much old mortar as possible from every crack using a brick chisel and hammer. The left side of the wall now appears to be in three sections. The top right section looks like it should pull right off, doesn't it? I wish! I thought all the hammering would loosen it, but nothing doing.....and keep in mind I cleaned mortar using blunt force trauma from all along the top, bottom and right side of this chunk as well as between the cracks. It's really starting to annoy me! Clearly, this section was pushed up (back slightly, too) during the collision. See how the leftmost bricks in the bottom two courses do not in any way resemble a straight line? Glaringly offensive to me! Ugh! I wanna walk, but I spent an additional 20 minutes trying to work just those two bricks loose. Nothing doing. I call a situation like this a BITCH!! - And I mean that in the worst way possible - just like a stubborn, unyielding woman (and OF COURSE I've been there and done that!), I knew if I DID push until I got my way, "she" would just find some other way to cause me more misery, probably something like this:

(May 13, 2005) - A 75-foot-high stone retaining wall built in 1908 collapsed in a roaring avalanche onto the Henry Hudson Parkway in Upper Manhattan yesterday afternoon. No one was believed killed or hurt, but parked cars were buried and traffic in the region was thrown into bedlam for the evening rush.The retaining wall, an ominously vertical landmark to drivers passing under its bulk just north of the George Washington Bridge at 183rd Street in Washington Heights, shuddered and rumbled and fell in two stages that terrified nearby residents and drivers who saw landslides falling on the road ahead.

- so I let it go.....btw: I considered using a power tool - maybe a dremel, but aside from the fact that I didn't own one at the time (I do now: Santa Carl got me one for Christmas - hey, thanks!), I doubt if I could have cleared enough space for a new brick.... this section of the brick was completely bonded to the interior wall and further demolition would have been necessary to correct it. Technically, even if my repair turned out to be a total failure, nothing was damaged that wasn't already damaged, so there could never be a liability claim. It's a safe vantage point when working w/o proper insurance.

The interior wall: let's have a look at this mess! Generally, a retaining wall built in this style would have a solidly constructed block and mortar interior wall which means the hollow concrete blocks would all be filled and the blocks would be securely bonded to the foundation and to each other. Strap ties (those corrugated metal strips) would be inserted every 2-3 feet between each course and later joined to the exterior wall in a similar fashion. Additionally, about midway up the wall, the examples I have examined have several drainage holes which go completely thru both walls, often with short pieces of 1/2 - 3/4" copper piping inserted. If the wall is over 4' there should also be welded steel reinforcement sandwiched between courses, and while that's not a structural issue here, I wonder if it should be considered even on low walls in "high traffic" areas. A brick veneer is not usually bonded to the block wall except at random points where excess mortar oozed between. Instead, they are joined with strap ties, resulting in a small air space between walls. Because there is always a possibility that moisture could seep into this air space, weepholes (usually nothing more elaborate than omitting or removing the mortar between a few perpends - ie. vertical joints) are placed in the bottom (or first above ground) course of the exterior brick wall. These are not so much for drainage, but more to allow the wall to breathe and moisture to evaporate. They also make cozy little niches for hibernating spiders! Anyway, I didn't notice any weepholes in the brick. Instead, it appears that the builder left mortar voids in the first course of the block wall, which doesn't really make sense. How can the wall breathe when it's buried in the dirt it's retaining? I didn't notice any drainholes either, but these are relatively minor concerns on such a small wall - it ain't like it's holding back a mountain on the Henry Hudson Pkwy!

Perhaps you're wondering WHY all this freaking rigmarole with the tie straps and the air space and the weepholes?? Wouldn't the wall be easier to build AND stronger if you just bonded the two solidly together with mortar? Well, duh! I'm trying to teach you stuff while I mull over how I should proceed with this repair. In this case, a solid build might have been fine. The airspace method is more appropriate for brick veneers built against wood or metal and has to do with differing contraction/expansion rates during extreme temperature changes. Had the interior wall been constructed of solid (poured into forms) concrete, even if sectioned for appropriate expansion space, I would have gone for the airspace. I'm pretty sure that a solid pack would have worked out ok in this case because the blocks are hollow, but filled with the same mortar used to lay the brick, and there are mortar spaces between each one. John Quick, my masonry mentor, does a lot of this brick over block work. I'll have to ask him what he's found to be the most successful technique.

Before I got to the actual repair, I had MUCH MORE blunt force trauma to inflict with my brick hammer and my dullerbytheminute chisel! I spent such a long time chipping away mortar from the wall, from individual bricks and small brick sections, from the concrete block rubble, and the busted up limestone cap - all as an attempt to salvage whatever original material I possibly could - that I learned a few things.