Domestic Property Smoke Alarm System

[James Simms]

I’m currently in the process of renovating my home. It is a 3 bedroom semi detached house and is ‘back to brick’ as such. It’s having a complete electrical rewire, new heating system and smoke alarms will be in all rooms, apart from the main bathroom and loft conversion en-suite. A LD1 or LD2 system from what I’ve looked at on the web?

 

On the building inspectors last visit she has sent me the site inspection report. She has stated in comments; Discussed mains operated Interlinked smoke detection to be installed in all habitable rooms at all levels within the circulation areas. Note that this is under the old regulations before changes to fire doors. Details required for the proposed doors which will require intumescent strips and appropriate hinges. Fire line board has been applied to the external face of the dormer with additional fire line board also proposed internally.

 

I started the works 2021, so before fire regulations were changed etc. So my question is, am I required to put intumescent strips on my doors in the house even though I will have smoke alarms installed throughout? The larger door casings would need to be installed to accommodate a fire door would they? 

 

I have fire boarded internally my dormer cheek now.

 

Any information or links I can be provided with would be greatly appreciated 

 

Thanks, James 

 

 

 

[Mike North]

I would suggest that the alarm for a semi is overkill, the maximum I would put in is an L3 with a CO detector wherever there is a gas appliance (unless there are vulnerable people)

Thanks to the loft conversion all doors (except for wet rooms) that are connected to the stairwell will need to be FD30S.

Unfortunately building regs do not allow for variation, once it is build you can then use the RRO to mix and match

[AnthonyB]

On 08/03/2025 at 07:42, James Simms said:

I’m currently in the process of renovating my home. It is a 3 bedroom semi detached house and is ‘back to brick’ as such. It’s having a complete electrical rewire, new heating system and smoke alarms will be in all rooms, apart from the main bathroom and loft conversion en-suite. A LD1 or LD2 system from what I’ve looked at on the web?

 

On the building inspectors last visit she has sent me the site inspection report. She has stated in comments; Discussed mains operated Interlinked smoke detection to be installed in all habitable rooms at all levels within the circulation areas. Note that this is under the old regulations before changes to fire doors. Details required for the proposed doors which will require intumescent strips and appropriate hinges. Fire line board has been applied to the external face of the dormer with additional fire line board also proposed internally.

 

I started the works 2021, so before fire regulations were changed etc. So my question is, am I required to put intumescent strips on my doors in the house even though I will have smoke alarms installed throughout? The larger door casings would need to be installed to accommodate a fire door would they? 

 

I have fire boarded internally my dormer cheek now.

 

Any information or links I can be provided with would be greatly appreciated 

 

Thanks, James 

 

 

 

Which country are you in - this has an impact as Scotland (& to a lesser extent Wales) do have different standards that may affect the validity of replies you get on here

[James Simms]

I’m North West England 

Thanks for the reply’s  👍🏽

[James Simms]

16 hours ago, Mike North said:

I would suggest that the alarm for a semi is overkill, the maximum I would put in is an L3 with a CO detector wherever there is a gas appliance (unless there are vulnerable people)

Thanks to the loft conversion all doors (except for wet rooms) that are connected to the stairwell will need to be FD30S.

Unfortunately building regs do not allow for variation, once it is build you can then use the RRO to mix and match

Thanks Mike. Obviously the said doors would then require fire casings too? 
 

Sorry, when you say about using RRO to mix and match? What do you mean by this? 
 

Thanks 

[Mike North]

Building regs looks at each element and tells you what you need to do. Using BS9999 would allow you decrease some fire protection by increasing others. The RRO also allows this by risk assessing the changes.  An example would be increasing the single travel distance by installing more fire detection in a building.

[AnthonyB]

On 13/03/2025 at 05:19, James Simms said:

I’m North West England 

Thanks for the reply’s  👍🏽

Then Mike is reflecting the current situation in English Building Regs guidance