BLD File

What are BLD files and how to open them

Are you having problems opening a BLD file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your BLD files.

What is a BLD file?

BLD files have multiple uses, and 3D Home Design Suite Model is one of them. Read more about the other uses further down the page.

3D Home Design Suite Model

We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

How to open BLD files

We have identified three BLD openers that are compatible with this specific type of BLD file.

Programs that open 3D Home Design Suite Model files

Last updated: August 24, 2026

All known file formats using extension .BLD

While 3D Home Design Suite Model is a popular type of BLD-file, we know of 2 different uses of the .BLD file extension. Different software may use files with the same extension for different types of data.

Skyscraper Simulator Building Script

Skyscraper Simulator Building Script files contain the instructions for defining 3D buildings in the Skyscraper simulator, a program for creating and exploring virtual skyscrapers. Such a file describes all aspects of a building's geometry, elevators, floors, textures, camera placement, and other settings so the simulator can generate the completed building when loaded.

These files are author-written plain-text scripts using Skyscraper's own scripting language. They are created and edited by users or building creators and saved with a name ending in ".bld". When placed in Skyscraper's Buildings folder, the software reads the script and renders the building defined inside it when the user selects "Other buildings" in the main menu.

Inside a Building Script, content is organized into sections like Globals, Floors, Elevators, Textures, Controllers, etc. Globals set metadata (Name, Designer, CameraFloor, CameraPosition, CameraRotation, version etc). Floor sections define each floor's height, walls, windows, ceilings. Elevator sections define their speed, serviced floors, shape and placement. Other commands load textures or include external script snippets.

Scripts must begin with ASCII syntax; the file is identifiable by its first byte (0x3C, which is "<", used for section tags like <Globals>) plus the presence of key reserved words such as CREATEELEVATOR, INTERFLOORHEIGHT, CAMERA (e.g. CAMERAPOSITION), ADDFLOOR, ADDWALL, END... etc.

While we have not verified the apps ourselves yet, our users have suggested ten different BLD openers which you will find listed below.

Various apps that use files with this extension

These apps are known to open certain types of BLD files. Remember, different programs may use BLD files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Help us help others

File.org helps thousands of users every day, and we would love to hear from you if you have additional information about BLD file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.