Entu expects to report a first half loss before interest, tax, depreciation and amortisation on continuing operations before exceptional items of around £2.2m-£2.4m.
It said that of this loss, around £0.7m was lost contribution in late March and April resulting from the constraints in fit capacity, offset partly by additional profit on the group's ECO-funded insulation business following a 15-month extension of its contract with a major utility company.
Net debt at 30 April was £6.5m.
Entu said sales in the core Home Improvements business held up well throughout H1, but the operational and supply chain difficulties meant that fit capacity in late March and April could not be scaled up enough to meet seasonal demand.
It added: "Driving up fit capacity to recover the lost contribution in the last weeks of H1 and meet seasonal demand in early H2 whilst the Group is addressing its complex operational and supply chain issues would be unsustainable and counter-productive.
"The group has, therefore, made the difficult decision to hold fit capacity at current levels and bring sales into line in order to protect levels of customer service until the supply chain issues have been resolved."