Filling A Gap Between Two Buildings
Filling A Gap Between Two Buildings
(OP)
I was asked to look at a five story building for damage caused by excessive moisture at the ground level interior walls. During the inspection I noticed that when the adjacent five story building was constructed, they left a two inch gap where, despite the flashing at the roof parapet, allows for water, snow and humidity to get in there. Since there is very little chance for any air flow and the sun can not reach the area to help dry it, the wetness penetrates the building. Furthermore, there have been complaints about rodents.
I am suggesting that they fill the gap to the top with concrete. Perhaps with fly ash or a mix that is less permeable. I would like to hear if anybody out there has any experience with a situation like this or any other ideas. Thanks.
I am suggesting that they fill the gap to the top with concrete. Perhaps with fly ash or a mix that is less permeable. I would like to hear if anybody out there has any experience with a situation like this or any other ideas. Thanks.






RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
Unless the two building's lateral load resisting systems are tied together (wich would seem like a difficult proposition to do properly) so that the buildings moved laterally together, the buildings will want to 'bang' into each other with all kinds of ramifications.
I would definately be looking for a different solution.
RE: Filling A Gap Between Two Buildings
Would suggest you do both. Concrete fill can create more problems than it will solve.
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
Take to a HVAC contractor, dehumanization thru ventilation may be way to get it (the wall) ready to receive further treatment. Or the devices can be left there permanently.
RE: Filling A Gap Between Two Buildings
how about constructing weep holes and air vents to allow the water out
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
Mike McCann
MMC Engineering
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
Even if you fill the cavity the water still needs to be kept out.
Filling the cavity will be detrimental to building movement and sound transmission.
I can't see it being possible to effectively waterproof a 2" x 5 storey cavity with a spray-on membrane.
RE: Filling A Gap Between Two Buildings
We grouted a small part of the cavity to provide slope from center to both sides (not 6' high...just enough to get 1/4" per foot slope), then waterproofed one side of the wall cavity (they wouldn't let us waterproof both sides because of the property fight!).
We are now putting a cap on the parapet of the old building and covering the gap at the top so that as little water as possible gets in (the buildings are different heights). They finally agreed that the cap could tie to both buildings, thus we have a fairly good seal at the top, but the waterproofing/sloping is a secondary measure.
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
Filling the gap with concrete is asking for trouble and potential lawsuit as any movement/ shifting by each building will tend to telegraph to the other.
The normal approach to this condition is to provide a flexible cap (prefab, aftermarket one is available) at the top of the walls and fill the front and back end vertically with an expansive or elastomeric material similar to an expansion joint detail. Architects normally specify this and if you have one as a friend, he could easily give you a brand name or you can look at a Sweets catalog.
RE: Filling A Gap Between Two Buildings
RE: Filling A Gap Between Two Buildings
This (waterproofing, sealing, expansion covers,etc.) is a job for a competent Architect. If you are a Structural Engineer - I would steer clear of specifying the fix. You should identify the likely problem (as you were hired to do) and recommend obtaining the services of an Architect or Waterproofing Specialist for the Fix Detail. They should be able to figure out the best way to fix this waterproofing issue.
RE: Filling A Gap Between Two Buildings