Paragraph 2603.4 provides requirements for how Foam-Plastic Insulation may be used inside of a building as a thermal barrier.
Question 1: When all of the requirements in Paragraph 2603.4 are applied, is it the intent to permit the use of Foam-Plastic insulation inside of an interior wall of a fully sprinklered building of any type of construction?
Question 2: Is it the intent that the requirements in this section, 2303.4, be applied only to foam-plastic material located on the outside of a building such as EIFS?
Question 3: If the EIFS material has a flame spread rating of 25 or less, must it still be encapsulated in accordance with section 2603.4 when used inside of a fully sprinklered building?
Interpretation #7952
Published July 27, 2017
Original Request
- Code Version
- 2004
- Code
- BUILDING
- Code Description
- Chapter
- 26
- Section
- 2603
- Topic
- Interior use of Foam Plastic Insulation
Question
Answer Published 07/27/2017 at 7:47 AM
Question 1: No. The referenced sections do not address interior walls. However, if the interior wall finish meets the requirements for a thermal barrier, it may be possible depending on the required type of construction of the building.
Question 2: 2303.4 addresses trusses and has nothing to do with foam plastic. Section 2603.4.1.4 addresses exterior walls of one story buildings and Section 2603.5 addresses exterior walls of any height. The answer to the question is no.
Question 3: EIFS is an exterior system and I do not see how it can be used inside a building. However, any foam plastic insulation is required to be separated from the building interior by appropriate thermal barrier meeting the provisions of Section 2603.4 unless special approval per Section 2603.8 is granted. One story buildings may meet the reduced provisions of Section 2603.4.1.4, but the foam plastic is limited to a maximum of 4 inches in thickness and it still must be covered thickness of not less than 0.032-inch-thick or corrosion-resistant steel having a base metal thickness of 0.0160 inch the building is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
Question 2: 2303.4 addresses trusses and has nothing to do with foam plastic. Section 2603.4.1.4 addresses exterior walls of one story buildings and Section 2603.5 addresses exterior walls of any height. The answer to the question is no.
Question 3: EIFS is an exterior system and I do not see how it can be used inside a building. However, any foam plastic insulation is required to be separated from the building interior by appropriate thermal barrier meeting the provisions of Section 2603.4 unless special approval per Section 2603.8 is granted. One story buildings may meet the reduced provisions of Section 2603.4.1.4, but the foam plastic is limited to a maximum of 4 inches in thickness and it still must be covered thickness of not less than 0.032-inch-thick or corrosion-resistant steel having a base metal thickness of 0.0160 inch the building is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
Commentary
None