Best Time of Year to Install Church Solar: Spring or Autumn

The short answer

For most UK parishes the optimal install windows are April-May (post-Easter) and September-October (post-summer holidays, pre-Advent). These periods avoid major liturgical seasons, harvest festivals, summer holiday programmes, Christmas preparations, and the worst winter weather.

For parishes with active hall programmes, install timing typically follows the hall use calendar rather than the church calendar — schools holidays often provide the best access windows.

Why timing matters

UK parish solar installations typically take 1-4 weeks on site depending on system size. During that time the install crew needs access to the church roof, the electrical cupboard, and the parish car park for scaffolding and equipment. Some disruption is unavoidable — and timing the install around major parish events makes the disruption acceptable rather than problematic.

Liturgical calendar considerations

Advent and Christmas (Late November-January 6th). Avoid. Carol services, Christmas Eve, Christmas Day, Boxing Day services, Epiphany services, plus Christmas tree, nativity, and decorations all complicate roof and electrical access. Some parishes have continuous Advent programmes from early December that run through Christmas.

Lent and Easter (Ash Wednesday-Easter Monday). Avoid the final weeks. Easter week (Palm Sunday through Easter Monday) involves substantial extra services, congregational engagement, and often extensive flowers and decorations. The four weeks before Easter are typically too pressured for major works.

Pentecost and Trinity (May-June). Acceptable for most parishes. Pentecost (50 days after Easter) is a significant feast but typically a single Sunday rather than an extended season.

Summer (July-August). Mixed. Some parishes have substantial summer programmes (children’s holiday clubs, summer festivals, weddings). Others have quiet summers with reduced services. Summer can work for parishes without hall children’s programmes.

Harvest Festival (September-October). Brief disruption only. Most harvest festivals are a single Sunday. The decorations come down quickly afterwards. Pre-harvest install is typically fine.

Ordinary Time (post-Trinity through Advent). Generally acceptable for installs except where parish has substantial autumn programmes (back-to-school in September, harvest in October, Remembrance Sunday in November).

Weather considerations

Spring (March-May). Good install weather typically. Days lengthening, temperatures rising, rainfall moderate. Generation begins increasing rapidly through May.

Summer (June-August). Best weather but worst for parishes with summer programmes. For parishes with quiet summers, June-July installs work well.

Autumn (September-October). Good weather typically. Most parishes most accessible. Generation begins decreasing but commissioning before December captures partial-year generation.

Winter (November-February). Possible but harder. Roof access more difficult in wet/icy conditions. Daylight hours short. Christmas and New Year disruption. Inverter and electrical work can proceed in any season but rooftop work prefers dry days.

Hall programme considerations

If the parish has an active hall with weekday community programmes, the install timing should respect the hall calendar:

School holidays. Most parish halls have substantially lower weekday use during school holidays (Easter, summer, half-terms, Christmas). These are often the best install windows.

Weekly programmes. Mother-and-toddler groups, lunch clubs, food banks, evening meetings — these recur weekly. Identifying the lowest-use day/days and scheduling install crew access around them works well.

One-off events. Weddings, christenings, funerals — usually known in advance. Install schedules can accommodate these.

DNO connection timing

G98 connections (sub-13 kW single-phase). 4-8 weeks from application to connection. Time the application to align with your preferred install window.

G99 connections (above 13 kW or three-phase). 8-16 weeks from application to connection. May determine your install timing more than parish calendar — sometimes the parish has to install when the DNO is ready.

We submit DNO applications as soon as contracts are signed (typically months 4-6 of a project), giving 4-6 months of lead time on the connection. This usually aligns the DNO with the preferred install window.

Faculty and grant timing

Faculty grant. Once granted, the faculty doesn’t expire (though most have a 12-month or 24-month implementation period). The install must happen within that window or the faculty needs renewal.

Grant fund cycles. Buildings for Mission, diocesan capital, Methodist Net Zero all have funding cycles. The award letter typically specifies an implementation period (typically 12-24 months). Install must happen within that window.

For parishes with faculty + grants confirmed, we typically schedule install for the next acceptable parish calendar slot within the funding implementation window.

A typical 12-month install timeline

For a parish that approaches us in January:

• January-February: Free desk feasibility, PCC discussion, initial vote
• March: On-site survey, formal proposal
• April: PCC votes to proceed; faculty drafting begins
• May-July: Faculty consultation, public notice, Chancellor’s grant
• June-August: Grant applications (Buildings for Mission, diocesan capital)
• September: Faculty granted, grants confirmed, contract signed
• October: DNO connection approved, install crew scheduled
• November-December: Avoided (Advent/Christmas)
• January-February: Install (sometimes scheduled instead of December)
• March: Commissioning, ready for full year of generation

This timeline avoids Advent/Christmas, Easter, and aligns commissioning with the start of the high-generation season. Modifications based on specific parish calendar are normal.

Faster timelines

For unlisted Methodist or free-church buildings without faculty requirements, install can happen 4-8 months after first PCC enquiry. We’ve delivered Methodist projects in 5 months from initial conversation to commissioning when the parish, grant funding, and DNO all align.

For listed CofE parishes, 8-14 months is more realistic. We work within whatever timeline the parish has, but managing expectations early prevents disappointment.

Practical recommendation

For PCCs considering when to start the conversation:

• January enquiry: install typically March of the following year (~14 months)
• April enquiry: install typically September of the following year (~18 months due to Christmas avoidance)
• September enquiry: install typically May of the following year (~8 months)

The September enquiry timing often works best because it gives 8-10 months for the project pathway, lands the install in spring/early summer, and captures most of the first generation year.

Request a free feasibility — including timing recommendations for your parish. See also our methodology page for the full project pathway and process page for the seven-stage breakdown.