Installing Z bar flashing under existing hardie help?

[Anna]

Hi all,

The flashing where the top portion and protruding bottom portion of the house was incorrectly installed when the house was rebuilt a few years ago. Our engineer advised us to have a siding contract install z-bar flashing (currently there is just a piece of metal on each side where water can easily blow back into the siding of the house). The siding is some knock-off version of Hardie board we believe, and given that it is already installed, we're trying to figure out our options without having to take down any existing siding and replace it with new siding. We were thinking we could take the corners off and slide the Z bar flashing into the siding from the side as I think Hardie typically is nailed from the top down, so there shouldn't be any nails on the bottom plank of the siding. Any suggestions/ideas would be greatly appreciated. Thanks in advance.

See here for the two areas of concern, they are located at the front of the house on either side of the portico: 

https://ibb.co/Csf2W2m

https://ibb.co/YkT5wLv

[Jim Katen]

To do this properly, the building paper under the siding has to overlap the z flashing. That's not possible to do by sliding it in from the side. 

Just remove the course of siding above each place you want to flash, install the flashing properly, and then replace the siding, typically using a pin gun. If you could remove the original piece without damaging it, great. If not, replace it with a new piece of siding. 

These kinds of repairs are done every day - it really shouldn't be too much of a trial for a contractor.