How do I kill black mold on cement exterior window sill?

Ask your local authority to send a building inspector. They will do it for free and will tell the builder what is wrong.

You don't fix a problem like that by removing a windowsill.

The roof should lead to just below a brick course and flashing should be inlet and cemented into that course of bricks.

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6:1:1

The lime helps it to spread and is similar to cement.

https://www.google.com/search?q=mix+ratio+for+rendering+exterior+wall

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Remove the door opening weather-strip. Refer to Door Opening Weatherstrip Replacement in Doors.
Remove side sill trim plate. Refer to Door Sill Plate Replacement in Interior Trim.
Remove the lower quarter panel trim. Refer to Rear Quarter Trim Panel Replacement in Interior Trim.
Remove the center pillar upper trim panel. Refer to Center Pillar Upper Trim Panel Replacement in Interior Trim.
Remove the quarter upper trim panel. Refer to Rear Quarter Upper Trim Panel Replacement in Interior Trim.
Remove the center pillar outer applique. Refer to Center Pillar Applique Replacement in Exterior Trim.
Remove the roof drip molding. Refer to Body Side Roof Drip Molding Replacement in Exterior Trim.

Important: It is necessary to use new nuts when reinstalling the quarter window.
Remove the nine quarter window nuts (1), securing the quarter window assembly (2) to the body opening.
Caution: When working with any type of glass or sheet metal with exposed or rough edges, wear approved safety glasses and gloves in order to reduce the chance of personal injury.
Important: When removing the quarter window from the body opening make sure that the attaching pins are clear of the outer body.
Remove the quarter window (2) from the body opening.

Remove the rear seat cushion. Refer to Rear Seat Cushion Replacement in Seats.
Remove the rear seat back. Refer to Rear Seat Back Replacement in Seats.
Remove the door sill plate. Refer to Door Sill Plate Replacement .

Remove the 3 quarter trim panel retaining screws (1).
Starting at the lower edge of the trim panel and moving alternately clockwise and counterclockwise, pull outward on the trim panel to disengage the eight rear quarter trim panel attaching clips (2).
Remove the quarter trim panel from the vehicle.
Remove the 4 radio speaker grille speed clips (1), securing the speaker grille.
Remove the speaker grille (2).
Remove the rear quarter trim panel insulator (1), from the back of the quarter trim assembly (2).
Remove 7 rear quarter trim panel armrest retaining clips (1).
Remove 7 rear quarter trim panel armrest retaining nuts (2).
Gently pry the quarter trim panel armrest insert assembly (3), away from the rear quarter trim panel and remove.

You mite look for a video on youtube !

It is located behind the right rear quarter panel , In the back right of the interior !
Remove the right rear quarter trim panel. Refer to Rear Quarter Trim Panel Replacement - Right Side in Interior Trim.
Removal Procedure

1. Remove the rear seat. Refer to Rear Number 2 Seat Replacement or Rear Number 2 50-50 Seat Replacement in Seats.
2. Remove the Third Pillar trim panel. Refer to Third Pillar Trim Replacement .
3. Remove the garnish molding. Refer to Body Rear Corner Garnish Molding Replacement .
4. Remove the door sill plate. Refer to Liftgate Door Sill Plate Replacement .
5. Remove the quarter panel trim screws.

A lot involved in this but not to difficult !

1. Remove the rear door sill trim plate. Refer to Front Side Door Sill Plate Replacement or to Rear Side Door Sill Plate Replacement .
2. Remove the lower rear seat belt cover and bolt.
3. Remove the trim panel from the vehicle.

Remove the sill plate. Firmly pull the sill plate up and out from the retainers.
Remove the sill plate from the vehicle. Start from the front of the door sill. Use a flat-bladed tool in order to pry the door sill plate.
Rear Side Door Sill Trim Plate Replacement
Use a flat-bladed tool in order to pry the door sill plate. Remove the sill plate from the vehicle.
Body Rear Corner Garnish Molding Replacement
Remove the rear upper garnish molding. Refer to Rear Upper Garnish Molding Replacement .
Pull down on the upper corners of the garnish molding in order to disengage the retaining clips. Pull in order to disengage the remaining retaining clips. Remove the rear corner garnish molding from the vehicle. Inspect the rear corner garnish molding for broken or missing retaining clips. Replace the retaining clips as needed.
Good Luck ! Fun job !!!!!

There is a short description about both-
Cement paint is water based paint and is applied to either exterior or interior including brick work and concrete.
Texture Paint, which may be manipulated by brush, trowel or other to give various patterns.

If your house doesnt have a roof ridge cap vent in the center all the way across the house then moisture will stay on the window pane and sill and cause mold and rott.

the factory manual calls it "side sill panel".

it's mold from the moisture, make a mix of 1 part bleach to 5 parts water and spray it, the black may not go away entirely but it will kill the mold.

this is an easy fix use 1 part bleach to 10 parts water and wipe down this will kill the mold you may need to do this several times

The molding in the middle of the door clips on. Remove interior door panel to access the clips, they usually break off. Or do you mean the black tapes (stickers) around the window opening, they are just stickers. Take a heat gun to loosen glue and peel off.