GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Fall protection on European Tilt N Turn Windows – Passing Code

Matt_Vetting | Posted in Building Code Questions on

We are trying to get occupancy on our energy efficient build. 

We have WASCO GENEO  Tilt N Turn windows. These windows are european style and turn inwards. The building inspector told us the upstairs windows need fall protection, so WASCO shipped out new handles which incorporate a button as a second requirement to open the windows. The inspector came and said that these handles have not been cleared for ASTM F 2090.

What to do…. has anyone found aftermarket fall protection devices for the windows explained above?

Here is the Minnesota Code 

R312.2.1 Window sills. In dwelling units, where the lowest part of the opening of an operable window is located more than 72 inches (1829 mm) above the finished grade or surface below, the lowest part of the window opening shall be a minimum 36 inches (914 mm) above the finished floor of the room in which the window is located. Operable sections of windows shall not permit openings that allow passage of a 4-inch-diameter (102 mm) sphere where such openings are located within 36 inches (914 mm) of the finished floor. Exceptions: 1. Windows whose openings will not allow a 4-inch-diameter (102 mm) sphere to pass through the opening when the opening is in its largest opened position. 2. Openings that are provided with window fall prevention devices that comply with ASTM F 2090. 3. Windows that are provided with window opening control devices that comply with Section R312.2.2. 4. Replacement windows.

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. qthisup | | #1

    I'm not sure of the dimensions of your window layout relative to code, but I'm based in Europe and typically these types of windows that are fitted close enough to the floor level to require guarding often have an external piece of safety glass installed up to the height required or internally a catch mechanism that limits the opening to 4" such as a window restrictor on a cable or latch, the latter can be released via a key sometimes or other mechanical means that a child can't operate.

  2. Expert Member

    Remember that any solution limiting how far the window can open may mean the opening will not meet code emergency egress requirements if the windows are located in bedrooms.

  3. GBA Editor
    Martin Holladay | | #3

    First of all, can you tell us your name? (I'm Martin.)

    At first, I thought that this was a question that was specific to tilt/turn windows. But upon reading your post, I'm inclined to think that this was an error performed by your designer. Your designer located the window rough-openings too close to the floor.

  4. Expert Member
    Michael Maines | | #4

    User-6841470, there are aftermarket devices for sliding, awning and casement windows that are made to address this requirement, sometimes called the Eric Clapton rule because he advocated for it after his kid fell out a window and died. In the IRC it's required when the window opening is closer than 24" to the floor, and more than 72" from the opening to the ground or another level surface. The devices are easy for adults to override, and safe in emergency situations.

    24" is easy enough to plan for, but 36" is high. Unfortunately I'm not aware of any made as aftermarket add-ons for tilt-turn windows; as Martin said, your designer should have allowed for this. I think your best bet is to add something on the exterior, as Quinn suggested--just make sure that the opening still meets egress requirements in your location.

  5. Matt_Vetting | | #5

    Hi, my name is Matt Vetting, for those of you who asked.

    David Paulus, the engineer with WASCO windows has been very responsive to our issues, but we are still getting the run around as far as inspection.

    We wanted to go with an exterior board or plexiglass, but the inspector indicated that the Minnesota ordinance is windows have to be 36" from the interior floor, which is not met by an exterior add on. Since we have a double stud wall, and deep window wells, the argument would be that a child could climb up on the window well and then hurl themselves out the window.

    I wonder if interior bars (openable by adult) to raise the window to 36 inches would meet the requirement.

    We think the two mechanism handles that WASCO windows sent us meets all the requirements of ASTM-F 2090-10, if not in spirit, but they really want to see an actual certificate for the actual handle. Sigh....

    It sounds like WASCO is willing to work with us and send us some replacement sashes that have an inoperable bottom (12 inches) and an operable top. To bring the inoperable portion up to 36".

    Just got word back that inspector would not accept the window guard option.



  6. Expert Member

    Meeting these sorts of requirements can seem onerous, but they are there for good reasons. My father did research into a specific type of brain injury. In all of North America he could only find three people who suffered from it, but he spent a years sabbatical in Glasgow, testing five of the city's inhabitants with the problem. Glasgow tenements traditionally have tall windows with low sills, that open outwards. Children push against them then tumble out. A simple regional difference that caused many injuries and deaths.

  7. Matt_Vetting | | #7

    I just wanted to update on what the final fix was for this problem. WASCO windows was willing to come out and modify the window (at no cost to us), such that the lower ~1 foot of the window was fixed, thereby raising the operable part to > 36 inches off the floor. WASCO windows has been great to work with and I would recommend them for their energy efficient windows.

    This is a cautionary tale though that issues of code compliance can slip by the architect, draftsman, builder, contractor and finally manufacturer so the homeowner needs to keep an eye out for these things also.

  8. Expert Member
    BILL WICHERS | | #8

    That’s really impressive that the manufacturer went so far to help you here when it wasn’t even a problem with their window (more of an architectural issue). I’m glad to hear you got things fixed so that you could get your inspector to sign off.

    For anyone doing retrofits for safety and not to meet code, I’ve used 1/4” polycarbonate panels to span up to about 2 foot windows and then set them into the frame like storms, or sometimes fasten them with keyhole slots milled into the plastic to hang on screws on the window frame. I originally did this for a set of windows for a client where their dog had been jumping against the windows and breaking the inner pane. Later on, the owner slipped and fell towards the window off a chair. The polycarbonate stopped his fall and prevented him from going through the window. Polycarbonate is far tougher than acrylic (plexiglas), so if anyone needs to construct a window barrier be sure to use polycarbonate and not acrylic.


Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |