Role: Senior Mechanical Design Engineer (Decarbonisation & Energy Solutions)Location: Manchester or London (Hybrid working available) Salary: up to £70k plus package The Senior Mechanical Design Engineer is responsible for the delivery of high-quality mechanical designs and technical support across decarbonisation and sustainable retrofit projects. This includes the design and optimisation of HVAC systems, heat pumps, and building automation systems, supporting the full project lifecycle from early feasibility through to construction and commissioning.What will you deliver?Strong technical grounding in mechanical building services design to integrate low-carbon energy solutions, such as heat pumps, heat recovery systems, high-efficiency HVAC, thermal storage, and demand-led controls for sustainable retrofit in commercial, public-sector, and mixed-use buildings.Proven experience in heat pump design and integration, including hybrid systems and low-temperature heating solutions.Ability to integrate mechanical systems with electrical infrastructure and low-carbon technologies for retrofit and new-build projects.Sound understanding of electrical building services to enable effective coordination.Competent in detailed design from RIBA Stage 2 to 5, including heating and cooling load calculations, ancillary equipment sizing and selection, ductwork and pipework sizing, schematics, schedules, DSEAR assessments, and technical reports. Participating and contributing to HAZOP and LOPA discussions/ meetings.Experience with heat networks and utilities, from feasibility through to applications and connection design.Proficient in AutoCAD and good working knowledge of BIM workflows (Revit desirable).Support energy modelling and system performance simulations using IES, Energy Pro, and other tools.Ability to lead mechanical design packages on multi-disciplinary projects.Ability to check, QA, and sign off mechanical designs in accordance with CIBSE Guides, BS EN standards, UK Building Regulations (Part L, Part F, Part G), and relevant industry codes.Design Management & Team DevelopmentUndertake design, coordination, and management, integrating mechanical and energy systems for seamless project execution.Produce and develop technical reports, drawings, and specifications.Comfortable leading client and contractor discussions, including technical presentations.Experienced in Design & Build and Traditional procurement routes.Able to mentor junior engineers and enhance team capability.Strong organisational skills, able to manage multiple concurrent projects and deadlines.Commercial awareness to support bids, scopes of work, and fee proposals.Assist in identifying design risks and contribute to risk mitigation, manage the risk registers.Project and Risk SupportManage designs and support end-to-end project lifecycle delivery, helping to ensure projects are delivered on time and within budget.Conduct design reviews, ensuring design solutions meet performance, safety, and regulatory standards.Senior Mechanical Design Engineer Experience:Experience in design and design management, risk assessment, and project delivery of sustainable retrofit, low-carbon technologies, and energy efficiency projects.Proficiency in design-, energy modelling- and simulation software such as IES, Energy Pro, PVsol, Termis, NEMO, and Netsim.Experience working across full RIBA stages on multidisciplinary teams.Experience in public sector or funding-driven decarbonisation projects such as PSDS and WH/ SHDF.Senior Mechanical Design Engineer Qualifications:Degree in Mechanical Engineering or Building Services Engineering (BEng or equivalent).Chartered Engineer status (CEng) or working towards.Strong experience in design management, risk assessment, and project delivery of sustainable retrofit, low-carbon technologies, and energy efficiency projects.Experience working across full RIBA stages on multidisciplinary teams.Experience in public sector or funding-driven decarbonisation projects such as PSDS and WH/ SHDF.Strong background in mechanical building services design, supported by practical experience or equivalent knowledge.What is on offer: Competitive salary, and benefit package, which includes;25 days annual leave (+ public holidays)Life Cover equivalent to 2 times annual salaryEmployee discount shopping schemes on major brands and retailersGym membership discountsCycle to work schemeHoliday purchase scheme2 corporate social responsibility days per yearBroad range of learning opportunities, such as professional qualifications, collective/individual training, and personalized support programmesAttractive Employee Referral Rewards SchemeAccess to our growing employee networks24/7 Employee Assistance Program and access to mental wellbeing appApplicationsIf you feel that you have the relevant experience to be successful in this position and would like to find out more please apply online today attaching a copy of your current CV. Alternatively contact us on 01474 850707. Howells are an Equal Opportunities employer. All applications will be dealt with in the strictest confidence. Howells acts as an Employment Business for the supply of temporary workers and an Employment Agency in relation to permanent vacancies. JBRP1_UKTJ