Refusal to let you in to do the gas safety check is a breachof the tenancy agreement, so your agents are correct in that.
However, you should make at least three documented attemptsto gain access, e.g.
- Send a standard letter making an appointment
- If they refuse the appointment, a second letterexplaining that the gas inspection is a legal requirement as is for theirbenefit as faulty gas appliances can be very dangerous – ask them to contactyou to make an appointment, if they fail to contact you
- Send a third letter asking them to contact youurgently
If you do this you will have done everything you can to gain access and will show that there is a clear breach of the tenancy agreement. I am going to presume the tenancy agreement includes a clause for inspections.
Not having a gas safety certificate will not cause you difficulties if you are issuing your s8 on the grounds of the tenant's breach of tenancy for failing to provide access. That would be a perverse element of the law, creating an impossibility of rectification. It would cause you issues if you tried to rely on a s21.
That said, you may be being a little ambitious with the hopes that you can get the tenant out by 13th September. Whilst you can serve notice, the tenant doesn't actually have to leave until you get a court order. Given you already seem to have a difficult tenant, I'd suggest he'll make getting him out as difficult as he can too.
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