Reinforcing Old Masonry Building
Reinforcing Old Masonry Building
(OP)
Looking at an old sandstone masonry building (built in 1894). The masonry and "mortar joints" have severely degraded over the years. The back wall is severly cracked throughout. Northwest corner has collapsed. Virtually no roof (giant holes throughout, several localized collapses). Second floor is the same. First floor framing above the basement is even rotten, heavily cracked, and completely gone in some locations. I did a structural inspection on this building two years ago (before the wall collapsed) and recommended demolition. I did this for the city, who did not own the property. I believe there were some legal actions take by the owner to prevent condemnation of the building at the time of the initial inspection. After the wall collapsed, the city stepped in again. I looked at it again, contacted an asbestos abatement demo contractor (there is asbestos in the building), produced demo plans, and obtained a demo bid. We live in a very small town....no options for contractors (the one I contacted is 100 miles from here). The city does not have the money to demo this building and has asked that I explore other options. I see none that I am comfortable with, but I understand the city's position. However, I want to perform my due diligence and explore ideas as requested. Does anyone have a reference they can point me to?
Also, has anyone reinforced a wall like shown in the attachment?
Also, has anyone reinforced a wall like shown in the attachment?






RE: Reinforcing Old Masonry Building
How to strengthen and preserve archaic building materials is a bit of an art. I don't have a particular reference for retrofits but I've used "Structural Analysis of Historic Buildings" by J. Stanley Rabun to help better understand some of the original conditions. For structural evaluations of the existing condition there are "guidelines" such as FEMA 304 thru 306 that can help you categorize the structure in terms of it's risk...but it sounds like this might already be apparent.
The detail you provided I'd describe more as an "encapsulation" than a strengthening. Basically it's a couple of layers of reinforced plaster. In its application I'd expect the existing masonry wall to be pretty sound from the start for the approach to be effective. Historic masonry can be rebuilt but care needs to be taken to use compatible materials. Mixing modern portland cement based mortar with old lime based mortar should be avoided.
regards,
Michel
RE: Reinforcing Old Masonry Building
RE: Reinforcing Old Masonry Building
Encapsulating the brickwork as proposed prevents 'wicking' the moisture from the building, and is not a real good idea. It can hasten deterioration. You do, however, have a few choices:
Demolition... easy and likely relatively cheap... building is lost... bad if the structure has some historical significance or Architectural significance.
Renovation... can be costly, more so, the amount of original material you want to keep... also requires an owner...
Restoration... can be more costly and it's a matter of stabilising the structure and undertaking repairs... good for a century type of building and my preference.
Stabilising... the structure can be stabilised until money is available to undertake Renovation or Restoration.
Good Luck... Dik
RE: Reinforcing Old Masonry Building
Dik
RE: Reinforcing Old Masonry Building
This brings us back to your question of tying in new masonry to the original, you'd like to keep them separate or provide some measure of resilience in the connecting element between the two.
Connecting floor and roof elements to old masonry can be challenging. Bearing joist/beams on the masonry in pockets and providing a steel through-wall tie with a backing plate on the exterior is most common. Not an attractive solution but effective.
regards,
Michel
RE: Reinforcing Old Masonry Building
RE: Reinforcing Old Masonry Building
From the deterioration noted, it appears that a poor quality of mortar was used in the original construction with limited hydraulic properties and over time, these have leached out leaving only the 'sand'... a not uncommon problem with historic brickwork.
The work ahead is detailed and expensive...
Dik
RE: Reinforcing Old Masonry Building
I wonder if you can find a building materials supplier who'd like to obtain an inventory of historical materials for the cost of deconstructing the building and cleaning up the site.
Mike Halloran
Pembroke Pines, FL, USA
RE: Reinforcing Old Masonry Building
I appreciate everyones' comments. I think my response to the city is still going to be that it has to be demolished.
RE: Reinforcing Old Masonry Building
Dik
RE: Reinforcing Old Masonry Building
RE: Reinforcing Old Masonry Building
RE: Reinforcing Old Masonry Building
RE: Reinforcing Old Masonry Building
RE: Reinforcing Old Masonry Building
RE: Reinforcing Old Masonry Building
RE: Reinforcing Old Masonry Building