How are chimneies (a chimney) attached to a house?

Question

I have a brick chimney, what methods are used by house builders to attach chimneies to the main house/structure?

Do the builders first create a wooden frame for the chimney that is nailed to the house?

I am going to be digging a trench at the footing of my chimney and would like to get a better sense as to how deep I can go without undermining the chimney.

Thanks

Answer 1

metal tie strips are attached to the studs on outside wall they extend out to between chimney block or brick and they lay between the mortor between each block layer.

Answer 2

a chimney is free standing, the structure only touches the lead flashing at the roof line.

i would stay far away from the footing of the chimney, if you undermine the footing you really can not repack it the same.

good luck

Answer 3

That depends on the structure of the house, the quality of the chimney work, etc.

In some cases they are NOT fastened to the house and are free standing.

In others, they are fastened with L shaped brackets nailed to the house siding and placed within the mortar between the courses of the brick.

In others, primarily internally located chimneys, I have seen the chimney itself used as a support structure for the roof joists.

On brick faced houses, they may be tied directly into the brick facing, free standing, or use L or Z brackets.

In ANY case, digging at the base of a chimney is NOT recommended, and IF it must be done, should be done by professionals.

Answer 4

the chimney if done right, should start at the original foundation footer. will be block until you reach grade then bricked being backed up by usually block if a working wood burning fireplace. if the house is brick cased, they will "tooth" the brick interlocking each course making it an actual integral part of the house.

if its just vinyle or wood, just wall ties will keep it to the wall. it should free stand if the house is gone so you should nt really worry about the footing unless the house is 100 yrs old.

Answer 5

As the chimney is built, the mason will periodically put in an "L" shaped bracket that is nailed to the house at one end and embedded into the mortar between the bricks at the other.  

They serve to keep the chimney from falling away from the building under moderate loads from wind, and minor earthquakes.    They aren't strong enough to support the vertical weight of the chimney if you dig under it to any degree, or if your trench slumps or collapses right near the footing.  

As long as the soil under the chimney is packed and dry, you should be able to trench near it, but I would be very quick about it - don't leave it long enough for the sprinklers to run or for the kids to flood the trench with water - just do what you gotta do and refill and compact that trench ASAP.