huangyhg

brick facade repair
are there any reference materials available that can assist me in putting some details together for the repair of the brick exterior wall of an eight story building? i noticed that there were a few small vertical cracks starting from the corners of the top floor windows and several step and horizontal cracks that are over ?" wide that go through the window lintels of the top floor. there seems to be crack in the mortar joints on both sides of the severely rusted steel lintels as well. of course asking to replace the brick facade all together is the an option but i would like to know what is being generally practiced out there.
thanks,

first, i would recommend an investigation to determine why the mortar or brick is cracked before you jump to repair method. is it simply rusty lintels or something more? if you have already done a thorough investigation, please share that information with us.
what is the age of the building? is it a load bearing building or a frame construction? is it brick with masonry or stud backup?
where is this building? has it been in a quake of 5.0 or higher since it was built?
mike mccann
mmc engineering
as jike has pointed out, there is no simple or general answer to your question. if you can give us some more details as to the construction of the facade, it may be possible to comment on some possible issues such as the corrosion of embedded steel elements, but a thorough investigation is probably warranted.
i was just exposed to the building and only know that it is about 80 years old in new york and that will likely have steel or block wall behind it. a few of the lower floor lintels have already been replace i guess since they could do it w/o scaffolding. the upper floor ones are all in bad condition. the roof , from what i was told, might have as many as seven layers and there are some areas of the top floor ceiling that are damaged due to water leak. i suggested taking a couple of cores to see what is there and what condition the roof deck is in. for the walls, it is hard to know what is there w/o actually removing the bricks. for lower floor is probably easy to find out what is behind the brick when replacing the lintels. for the upper floors however, the only way to get real close is when the scaffolding is up and that is something the client wants to know.
i also think that the freeze-thaw and water damage in addition to age are contributing factors not mentioning lack of maintenance.
so, i am looking for some guidance on the course of actions and if there are any routine or standard approach for this type of problem which i am sure is not unique to this building.
thanks,

investigation of building envelope failure is a fairly specialised area of practice, and the firms which do this work tend to have a variety of experts on staff. each project would require detailed planning for the investigation, including all the access requirements necessary to get to the problem areas. if your firm has not done this type of investigation, it may be better to seek a partner who has the requisite experience.
you could make your investigation part of the brick removal and replacement program. it sounds that at the least, the lintels will need to be replaced. when they remove some of this brick schedule a site visit and get up there on the scaffolding and see exactly what is going on behind the brick. the following questions should be on your mind:
- are all the ledges rusted?
- what is tieing the brick back to the wall system?
- why are the cracks appearing at the top corners?
- is the public in danger of falling brick?
new york city has a requirement that brick facades be investigated by an engineer every 2? years with recommendations for immediate, soon and eventual repairs.
for a lot of practical and monetary reasons, i would disagree with teguci as to combining the investigation with a contract to replace lintels. once the lintel replacement contractor is mobilized, you would be under pressure to decide on any further required work, design the work, and contract for the work. the contractor would have you over the barrel. best to do a full investigation and design rectification methods before construction is started. if the full extent of required work is still not known, you could use a unit price contract, but at least the activities you know about would be defined.
determine the cause, first. then a matter of undertaking the work to correct.
if just old age corrosion then it's likely a matter of replacing all lintels and the scope should reflect this.
dik
if the lintels are corroded, the relieving angles and wall ties would also be suspect. if there is any bulging or crushing of brick, growth could be an issue. just things to look for.

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